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 Independent Home glyph: home, sun, wind, water

The New Independent Home

     by Michael Potts


(numbers in parentheses are chapter references)

100th Monkey : According to the story, a group of forest-dwelling monkeys living on one of the small islets fringing Japan's northern island of Hokkaido were being studied by scientists who fed them rice to entice them to move their operations into more open stream-side beach habitat for observation. The rice mixed with the coarse beach sand where it was sprinkled, and the monkeys spent hours separating rice from sand . . . until one of the elder females discovered that when a handful of sand and rice was put in the water the rice floated and the sand sank. Her grown daughter and daughter's female offspring quickly learned the trick and prospered, and soon most of the colony's sixty females were also separating rice using water. The senior males steadfastly continued their old ways, and younger males were also slow to adopt new methods, but over the years the number of practitioners rose until the hundredth monkey adopted the technique. Here's where the phrase "100th Monkey" comes in. At about this time, all the rest of the monkeys in the troop began washing the sand out of their rice, and on neighboring islets other troops of apes spontaneously began the practice.
     Anyway, it's a great story. (16)

2x6s : one standard size of lumber, nominally 2 inches by 6 inches. In half a century the actual thickness has diminished from 2" to 1-3/4" to 1-5/8" to the present measurement of 1-1/2". (2)

6-6-10 reinforcement : a flexible metal concrete reinforecement screen woven with 10-gauge wire 6 inches apart in both dimensions. (8)

adder : the term used by utility regulators to calculate the per-kilowatt cost of a system-wide expense -- see externalities adder. Second meaning: what the snake objected when bid to go forth and multiply -- "We can't; we're adders." Necessitating the invention of logs... (14)

afterbay : the pool below the hydroelectric generation plant where the water "borrowed" to spin the turbine is reunited with the stream. (3)

airfoil.gif - 2801 Bytes airfoil : a shaped blade or (more commonly) wing designed to provide lift. When a moving fluid (like air) is split into two streams by a blade, and one stream travels farther, the pressure on that side is reduced by the Bernoulli effect, and the blade tends to "lift" into that stream. (9)

allelopathic : an interaction between species in which one or both interfere with the processes of the other. In plants (like the eucalypts or bolting lettuce) this is often accomplished by production of a material tolerable to the producer but poisonous or unpleasant to other life forms. (11)

alpha rhythm : brain waves in the 8 to 13 cycles per second frequency range, usually typical of a normal awake person in a quiet resting state (16)

sinewave.gif - 2404 Bytes alternating current (AC): electricity that changes voltage periodically, sixty times a second (or fifty in Europe). This kind of electricity moves more easily than direct current (DC).

alternator : a form of generator that produces alternating current; common in modern automobiles (3)

ambient : the prevailing temperature, usually outdoors

amorphous : "without form" -- often used to describe the chaotic silicon lattice of thin-film PV modules (3)

amortize : paying a debt over time in small periodic installments which typically include interest (16)

amp : short for ampere, the unit used to measure the instantaneous flow of electrons, theoretically, 6.02x1023 electrons.

amp-hour : measure of a batteries ability to sustain a flow of energy over time; 60 amp-hours indicated a battery can deliver one amp for sixty hours.

animist : one who believes that everything, animal, vegetable, or mineral, possesses a soul or spirit (13)

anode : the electrode (in a cell) toward which negative charged ions are drawn. (4) ????

appliance : "a thing used as a means to an end", a machine to achieve some useful purpose, such as keep beer cold or make music. (1)

architect : from the Greek "chief builder"; "A person skilled in the art of building; one who understands architecture, or makes it his occupation to form plans and designs of buildings, and superintend the artificers employed." (Webster, 1828) (1)

architecture of dominion : building as if humankind ruled everything

Ark, the : Noah's boat, or by extension, any isolated and apparently floating repository of rare and endangered life forms, for example, the Hawaiian island of Maui. (4)

audit : a careful reckoning; an energy audit ascertains the flow of energy over time, and seeks and prioritizes economies.

average-watt : the wattage consumption of an appliance or operation averaged over a long period. Appliances often use more energy when starting. (16)

avionics : electronic equipment in the service of aviation (16)

avoided cost : the money saved by the utility because it is able to use a cheaper source; the minimum amount set by PURPA legislation that utilities were obligated to pay independent power producers. When this idea originated during the Carter era it was meant to define the whole amount utilities might avoid paying by buying surplus electricity from small power producers: If, for example, the utility could use clean renewables instead of buying OPEC oil, it might also be able to avoid paying for transporting and storing the oil, and cleaning up the combustion pollution. If the replacement source was deemed sufficiently abundant and stable, the utility might even be able to avoid paying for building a new oil-fired power plant, in which case the avoided costs might be substantial. During the Reagan era, utility interests weaseled the definition to exclude all factors but the cost of the oil. Ironically, many in the renewable energy business believe that their industry is stronger because it grew without government subsidy and intervention. (14)

back-to-the-land : a social movement in reaction to urbanization, in which people leave their "civilized" jobs and homes in the city and its suburbs and seek to return to a simpler, more pastoral life (1)

bagasse : the sugar cane after the sugar is squeezed out, a fibrous material which can be used to fire boilers to produce steam to spin turbines to generate electricity (1)

balance-of-system : equipment that controls and measures the flow of electricity

barostat : a device which opens or closes a switch depending on the barometric pressure (see picture, 2)

base-load electricity : the smallest amount of electricity consumed by a utility's customers. Baseload is provided by slow-to-start, relatively inexpensive-to-operate generators, while peak-load is provided by quickly dispatchable sources. (4)

battery : a collection or grouping of similar entities, hence a battery of artillery, or of tests. In electrical usage, battery correctly means a collection of cells, but is often misused to mean a package containing one or more cells. (2)

battery charger : a device meant to apply electrical current to a battery or collection of cells in order to store electricity. (12)

belt-and-suspenders : redundant systems (9)

berm : earth mounded in an artificial hill (8, 11)

bioengineering : using engineering techniques to "improve" life (as in designer crops or genetic engineering), or applying biological techniques to accomplish manufacturing work previously done by fabrication (heat, beat, treat). (1)

biomass : wood, bagasse, indeed any mass (usually combustible) created by biological processes (2)

biosphere : the thin layer of air and water that supports life (6)

BLM : the federal Bureau of Land Management (9)

blackwater : used water out of a toilet or other grossly unsanitary source (7, 13)

blower door : an adjustable panel that blocks a doorway in a house, fitted with a fan controlled by a barostat. (2)

blower test : a test of the leakiness of a house conducted with a blower door. (4)

boule : a barrel-shaped single crystal of purified silicon or other semin-conductor metal. The thin wafers of silicon used in photovoltaic cells and integrated circuits are cut from the boule using a thin diamond-bladed saw. (3)

bridging fuel : a fuel available in limited quantity that can be used to "bridge" the time required by technology to discover a better source. Petroleum is considered by experts to be a bridging fuel, and atomic power was supposed to be an unlimited source. (1)

BTU tax : an often-proposed means for rewarding conservation by taxing consumers for every BTU of fossil energy consumed. (16)

bus-bar cost : the price of electricity at the point of delivery; for most of us, the retail cost. (16)

caliché : a very light, almost white-colored adobe; sources of unusual colors of adobe, including black and blue, are often treasured trade secrets. (8)

carcinogenic : cancer-causing (1)

carcinogens : substances known to cause cancer; benzene, a by-product of combustion of natural gas and propane, is a carcinogen. (13)

cathode : the positive plate in a battery (4) ????

caulking : goo pumped between ill-fitting parts of a house to discourage water from infiltrating. The goo comes in a number of colors, compositions, and abilities to adhere to glass, wet wood, plastic, paint, and metal. Caulking in most cases cracks or shrinks, and so the process must generally be repeated periodically. (2)

cell : the smallest self-sufficient working mechanism. A single-celled animal is thought to have been the first life form. A solar cell is a single slice of doped semiconductor and supporting hardware that produces a voltage determined by the chemistry of the semiconductor; the larger the cell, the greater the amperage, but the voltage remains constant. A storage cell in a battery is usually a container full of electrolyte plus a cathode and an anode that also produces a voltage determined by the chemistry of the cathode, anode, and electrolyte; as with the solar cell, a larger storage cell will produce more current, but the voltage remains roughly constant. (2)

centrifugal pumps : mechanisms for moving fluid by centrifugal force. The fluid enters near the axle of a rapidly-spinning impeller, and is impelled away from the center. Since the fluid dynamics in around the spinning impeller are typically chaotic, centrifugal pumps are inefficient. (9)

CEO : Chief Executive Office. Others in this family of acronyms are CFO (Financial), COO (Operating), CIO (Information), and MIS (Manager of Information Systems) (16)

charge controller : the device in a stand-alone energy system that feeds electricity from the source, typically a PV array, to the battery bank. The charge controller protects the batteries from overcharging. (4)

charge gradient : an electrical "slope" created by mingling ("doping") a semiconductor with atoms that give up or take up electrons more readily than the base material. To a free electron, such a gradient looks like a hill to roll down, away from the negative and toward the positive. (3)

circuit breaker : an automatic switch that senses too much current and turns off. Fuses perform the same function, melting when too much current passes through the fusible element; unlike fuses, a circuit breaker can be reset many times after it cools off and the overcurrent condition is corrected. (4)

circulating hot water : a design for the impatient: hot water is delivered to a whole household through a loop through which the hot water is circulated by a pump. Even if the loop is well-insulated, it radiates considerable energy, and the pump also uses significant energy. The benefit? Well, in addition to the utility making extra money, and the extra pipe and frequently-replaced pump, householders enjoy more-or-less immediate hot water when they turn on the tap. The typical circulating hot water system consumes roughly three times as much energy as a "static" hot water system. (2)

CNC : Computerized Numeric Control, in reference to milling equipment that can be programmed to form complicated curves. (9)

CNG Energy Index : Consolidated Natural Gas Company, a national enterprise, has commissioned this index to estimate the comparable costs of comfort in the United States. (2)

collector : anything that collects -- but you already knew that! In the solar world, a collector harvests solar energy, sometimes by heating water or any transfer fluid, sometimes by heating air. Technically, PV modules aren't collectors; they're modules. (1)

compact fluorescents : a fluorescent light about the same size as a light bulb, created by folding a small diameter tube; a compact fluorescent usually also includes the electronics that convert house current to the pulsed high voltage electricity that excites the phosphors in the tube. In a typical fluorescent fixture, the electronics (called the ballast) are separate from the tube. (1)

comparables : in real estate, similar properties that have been sold recently. Because an off-the-grid home's energy system changes many of the fundamental costs of ownership, and because independent homes are seldom sold, finding comparables for such a home may be difficult. Since bank loans are often based on comparables, this makes financing off-the-grid homes more difficult. (6)

compost toilet : any toilet designed to make the unmentionables go away by composting them, usually along with grass clippings, sawdust, or moss. (1)

conduction : one of the means whereby a quality is carried through a material (convection and radiation are two others). Heat conduction takes place when energetic (hot) molecules bounce off of lower-energy molecules, thereby transferring some of their energy. Heat can be carried by conduction through solids -- that's how the stove heats the water in the teapot. A material's resistance to conduction is measured as its R-value. Electrons can also be conducted through a wire or other conductor by moving from atom to atom; in this form of conductance, the resistance is measured in Ohms. (2)

conserve : to use as little of something as possible, so that the balance may be preserved unused, or so that a finite supply can last as long as possible. (1)

consumer : one who consumes. In this book, this is used in two ways -- we are all consumers, in that we consume oxygen, food, and so forth, but in this book "consumer" is used in a pejorative sense to denote someone who consumes for the sheer sport of consuming. In this sense, a jet-ski is a perfect consumer item. (1)

convection : a process whereby a quality is carried through a material (conduction and radiation being two others. Convection can be observed (by adding a marker such as incense) in the way heat moves through the air of a room -- generally, colder air falls, causing warmer air to rise because it is lighter, its molecules being more energetic and farther apart. (2)

conversion : any process in which one form of energy is converted into another -- for example, a generator converts spin (mechanical, rotational energy) into a flow of electrons (electrical energy). (2)

conversion losses : conversion of one form of energy into another is invariably imperfect in the sense that the amount of energy produced in the new form is less than the original energy. The lost energy reflects the efficiency of the conversion, and is termed "conversion loss". By looking at all the conversion losses between source and final desired effect, the sum of all the conversion losses defines system efficiency. An internal-combustion driven automobile is an extremely inefficient system. Neglecting inefficiencies in extracting, transporting, and refining the fuel, and handling the pollution caused by combustion, a typical automobile converts about 30% of the original energy in the fuel it consumes into motion. The litany of inefficiencies includes conversion from liquid to gaseous fuel, heat inefficiencies at combustion, mechanical inefficiencies in converting from linear motion of the pistons to the rotation of the tires, rolling resistance. Inefficiencies are compounded by the changes in speed and direction that constitute driving. Including conversion losses from cradle to cradle, from petroleum in the ground to the final resting place of vehicle and all its combustion byproducts, conversion losses in an automobile may be as much 95% of the original heritage fuel consumed. (16)

convert : to change form. To change the form of energy from chemical (in a battery) to electrical invariably costs a share of the original energy. (2)

cost-effective : an accounting term that describes a process wherein the overall value of its benefits are greater than the sum of all its costs. (2)

cotton scale : a tiny insect pest with a carapace shaped like a fish scale (16)

CRI : Color Rendering Index -- a measure of the faithfulness of color perception as compared to sunlight. Under certain conditions, unfaithful color rendering is desirable, as for example over the salad bar, where lights are chosen to accentuate the greens. (4)

cross-linked polypropylene : high grade plastic in which the molecules are tightly linked with each other, making them less likely to link with external materials that might weaken the plastic. Such plastics have a much longer life expectancy and are preferred for food-grade use. (8)

current : flow. In a river, the current is usually strongest near the center where the river is deepest. In electrical terms, current means the electrons flowing through a conductor, and is measured in amperes, one amp meaning 6.02x1023 electrons. (2)

curtain-wall : a building with glass on the outside and the structure within; to survive a hot afternoon in such a people-cooker, curtains will be handy. (2)

cutting windspeed : the speed at which a wind-spinner's blades start making a noise loud enough that it carries upwind and annoys the neighbors. The noise is due to chaotic, non-laminar flow around the blades, caused in some cases by the airspeed of the blade tips breaking the sound barrier. (9)

dead dinosaurs : a flippant term for fossil fuels. In fact, most fossil fuels were laid down hundreds of million years before the dinosaurs. (1)

deciduous plantings : trees and shrubs that are leafy in summer when shadow is welcome, but lose their leaves in winter, allowing more light to pass through their bare branches. Deciduous plantings on the western side of a house reduces heat build-up that makes some houses unbearably hot during long summer afternoons. (2)

degree-days : a measure of the need for heating and cooling; one heating degree-day calculated at a base temperature of 68F would mean that the outdoor temperature averaged 67F; ten heating degree-days would mean that the average outdoor temperature would be 58F. Degree-days are usually accumulated over months and years to describe a climatic regimen. For example, Fairbanks, Alaska, "enjoys" 13,940 heating degree-days a year, but in the warmest month, July, only about 160 degree-days of heating are required. Only 200 heating degree-days must be supplied to maintain the base in Miami, Florida, but 4,198 degree-days of cooling are required. (2)

distributed intelligence : an idea from information technology, meaning that a system's operating decisions are not made in a single central place, but are being made throughout the system. (16)

doping : a chemical process essential to the fabrication of semiconductors, in which "impurities" in the form of atoms of electrically active elements are introduced into the pure semiconductor matrix. Phosphorus, Gallium, and Selenium are common dopants. (3)

drip irrigation : a technique for delivering irrigation water precisely at the point of need, thereby reducing the amount of water (and hand-watering) required. In practice, lots of plastic tubing is looped amongst the plants, and must be taken up and thrown away annually for efficiency to be maintained. Planting appropriate native plants that require no irrigation is more cost-effective. (1)

(service) drop : generally the wires that swoop in from the powerline to the service head above the electric meter; any connection between utility distribution and consumer metering. (16)

Edison cells : an early commercial battery pioneered by Thomas Edison, using nickel and iron. (1)

efficiency : a concept based on the question, "How much of what went in came back out?" In an efficient system, you get back as much as you put in. In physical systems there is usually a tangible cost, or a conversion loss, which reduces efficiency. See the entry for "conversion losses" for a fuller discussion of efficiency. (2)

electrical co-ops : Beginning as cooperative organizations sponsoring electrification, particularly in the 1930s, electrical co-ops have matured into a rare (in the U.S.) but successful and efficient means for providing electricity. (3)

electricity : a flow of electrons providing usable energy. Because no one has ever seen an electron, there is a mythical quality to the theories attributed to electricity, but anyone who has grabbed a hot house-current wire can attest to the reality of this kind of energy. (2)

electrification : bringing electricity to the users -- the term is mostly used in the context of Rural Electrification programs popular during the 1930s. (1)

electrolysis : a chemical process in which the hydrogen and oxygen atoms in water are separated by the application of electricity. (4)

electrolyte : "battery juice"; in lead-acid batteries, more-or-less dilute sulfuric acid. Consumer batteries use a solid electrolyte made up of filler impregnated with chemicals. The electrolyte allows ions to migrate to the battery's anode and cathode and react, producing a flow of electricity. (4)

electrons : mythical beasties that purportedly occupy the region surrounding the atomic nucleus. There whereabouts are unknown and presumed to be unknowable, but their group behavior is predictable, allowing us to enjoy the Electronic Age. Large numbers of them flowing together comprise electricity. See also "current". (2)

EMR (Electro Magnetic Radiation) : Whenever electrons flow, a magnetic field is created, whether it be around the nerves in our bodies or around the high-voltage powerlines that criss-cross our land. Nobody has yet proved one way or the other, but there is evidence that suggests that long-term exposure to strong electromagnetic fields is not good for living things. Because so much is at stake, emotions run very hot on this; the apologists for the utilities say "no problem" and the advocates of purity say "HUGE problem". While they fight it out, I keep the big dirty radiators, such as electric blankets and inverters, at a distance from where I live, work, and sleep. EMR can easily be measured with a meter designed for that purpose. (2)

end user : that would be you and me, friend: we may also be called "the customer" or "the consumer" or "the client" or "the patient" but you always know that when they start talking about you as if you don't have a name and aren't there, they're preparing to do something inhumane. (2)

end-use losses : inefficiencies in the household or place of business that are paid for by the customer, as distinct from transmission and distribution losses that are absorbed by the utility. (16)

envelope : a membrane that encloses something; when speaking of a building's envelope, the outer skin of the building. (2, 7)

environmentally friendly work : work that may be carried out without damaging the biosphere in any way. Information work -- typing letters, entering and manipulating data, doing research on the internet or in the library -- is normally benign (unless you are wearing offensive perfume) but without great care, extractive work -- digging coal, mining gold, felling trees, or even harvesting the corn crop -- tends to be unfriendly to the environment. Experience shows that with proper care almost all work can be performed in an environmentally friendly way, although caring for the environment adds so much overhead that some works become uneconomic. Then the question must be asked: Do jobs and short-term human issues justify long-term environmental harm? (1)

equalizing : a periodic, systematic overcharging of batteries to make ensure that every cell comes up to full charge and is pulling its weight. (4)

equipment cost : the total sum expended to purchase the hardware. This term is usually used together with "operating cost" or the cost to operate the equipment. A car might cost $10,000 (equipment cost) but over its useful life might consume as much in fuel and half as much in maintenance and repairs (operating costs). In this case, equipment costs represents only 40% of total cost of ownership. (1)

eschatology : the study of the end of the world. (16)

externalities : cost considerations other than those normally accounted as cost. A typical externality is the health costs incurred by respiratory patients in communities downwind from and under the plume of a large, dirty coal burning electricity generation facility. (1)

externalities adder : an arbitrary and generally insufficient charge to get the externalities back into the accounted costs. In Vermont, it looks like 30% must be added to the cost of electricity just to cover the health costs of dirty generation. (2, 14)

face time : a term used to describe the time that many employees, and particularly bosses, need to have "face to face" with their co-workers. Work-at-homers must often plan for activities at the office to get enough face time with their associates and supervisors. (12)

false economy : something that looks cheaper than it really is. False economies result from buying things that almost fit because they are on sale -- cheap windows, for example, may cost 40% less installed, but over their lifetime leak energy worth ten times the saving over better windows that cut that leakage by two thirds. (1)

ferroconcrete : a construction technique using iron-reinforced concrete usually to build water tanks and boats. (1)

fifteen-light door : a wooden (or, sometimes, metal) door with five rows of three windows ("lights" in the fenestration business). (7)

first-growth : trees that have never been harvested. An "ancient forest" of old growth redwoods may have been undisturbed for three millennia. (7)

fission : splitting the nuclei of atoms. (2)

flat discount rate : accounting for the cost of energy as if the small user and the very large user contribute equally to the cost of generation and transmission infrastructure. (16)

fleet mileage standards : the federal mandate that American automakers should work to improve the efficiency standard of all their passenger vehicles. The idea was shot full of holes from the start -- notoriously fuel-inefficient and dangerous (but yuppy-approved) Urban Assault Vehicles (SUVs) were specifically excluded from the "fleet", giving rise to a market wherein one of every four new cars is an SUV. The automakers couldn't make as much selling efficient cars, so they used advertising to reshape their market. (2)

floats : Of a power system: the "ground potential" is allowed to float, without any earth-supplied "absolute zero"; the only thing known for sure is that the positive side is nominally 12 or 24 volts DC more positive than the negative. This is standard practice in Europe, and works well. In the U.S.'s belt-and-suspenders regulatory environment, much is made of bonding the equipment to a unique "true ground". Of a battery: when not much energy is being taken out of storage, and the charging source keeps the batteries "topped off" at full charge, the charge controller "floats" the batteries. (4)

flush toilet : the kind we're used to, where you depress a lever and 1.6 or more gallons of potable water flushes the unmentionables away. (1)

forebay : the pool above a hydroelectric generation plant from which it draws water. The water travels through a headrace where it enters a penstock and flows to down the turbines, then debouches into the tailrace and the afterbay. (3)

knifeswitch.gif - 2403 Bytes Frankenstein knife switches : big mechanical switches with one or more conductive blades connected to an insulated handle. When switched "on" the blades fit between spring-loaded receivers to make contact. (1)

fuse : a carefully designed metal conductor that melts (fuses) if too much current flows through it. Fuses are usually encased in glass or ceramic so if they "blow" enthusiastically, they will not splatter bits of molten metal. (4)

Gaia : the name for the large planetary organism which includes all life on earth, including us. The Gaian Hypothesis suggests that all life forms are interdependent and linked together so that whatever is done to the smallest finally affects everything and everyone. (13)

gen-set : shorthand for a motor-generator pair, usually a small gasoline motor and house-current generator. (3)

generator : a device that converts mechanical, rotational energy such as might be produced by a water wheel, turbine, wind-mill, bicycle crank, or (worst case) an internal combustion engine, and converts it into electricity by spinning a coil in a magnet field, or vice versa. (2)

geothermal : correctly used, this refers to energy derived from steam trapped below the ground, often in volcanically active areas like Yellowstone and California's Geysers. Steam wells are drilled and capped, and the steam is made to drive turbines as it escapes. This term is also sometimes used incorrectly to describe the inefficient practice of pumping heat into uninsulated ground during the summer, then retrieving it in the winter. (3)

gnomon : the indicator on a sundial. (8)

golf-cart batteries : 6-volt batteries designed to withstand the deep-cycling of a golf cart, discharged for 18 holes, then recharged, repeatedly. Such batteries are fairly good for storage in a solar-powered home energy system. (1)

gotcha! : the unanticipated consequence; what the fisherman says when he sets the hook. (2)

gradient : a steady slope, or, in electricity, a charged field that changes more or less linearly with distance, typically a very small distance across the thin dimension of a semiconductor. (3)

Grand Coulee : a very wide concrete dam on the Columbia River in Washington State. (5)

gravity flow : if our water supply is sufficiently above our point of use -- the showerhead, for example -- then no energy needs to be expended to set the water flowing. For each 2.1 feet of elevation, 1 pound per square inch (psi) is generated, and we Americans like a 20 psi shower, so (with a little for pipe friction) a 50 foot tower gives us the gravity we need. (1)

greywater : not as nasty as blackwater, greywater is all the other kinds of waste water except from the toilet -- kitchen sink (if you don't cut or wash meat, fish, or other putrescibles), shower water, lavatory water, laundry water are all shades of grey. If you think about it, you'll understand why, in a zero-defects sanitary regime, all waste water is treated as black. When necessity (in the form of too many people and not enough water) intervenes, grey water can be handled safely, and great gardens result. (1)

grid, the : the network of electrical transmission and distribution lines that link 99+% of the homes in the U.S. and Canada. (1)

grid-excited inverter : an inverter changes DC electricity -- the kind that comes out of PVs -- into AC or house current. A grid-excited inverter, which is connected to the power grid and exports locally-harvested electricity into it, only operates when the grid is energized. (16)

half-life : a chemical term that describes how certain active chemicals lose half of their activity over a characteristic period of time, the half life. Radioactive materials "decay" in this way, some with half-lives measured in the nanoseconds (billionths of a second) and others much longer. Plutonium's half life is just over 22,000 years. (1)

haole : Hawaiian for white non-native. (9)

head : in hydro, the elevation of the intake over the generator. (3)

headrace : a channel connecting the forebay to the entrance of the penstock. (3)

Heisenberg : a physicist who hypothesized that certain phenomena cannot be measured without interfering with them. More specifically, he suggested than an electron's weight might be measured, but not its location, or its location but not its weight. So far, research shows that Heisenberg was right. (2)

heritage fuels : part of the greater endowment of heritage materials that make the planet earth such a rich and varied place. Heritage fuels, also called fossil fuels -- coal, petroleum, and natural gas -- represent a surplus of carbon on the planet that took Gaia 300 million years to get safely stored underground. Humans have dug up and burned about half of the petroleum, a third of the natural gas, and a quarter of the coal in about 100 years. The joke may be on us when we discover that some essential material -- a treatment for cancer? -- can only be made with the heritage fuels we burned up hastily in pursuit of easy wealth and cheap energy. (1)

high-tech glass : the best fenestration that money can buy, usually two (or even three) layers of glass, or two layers with a plastic inner film, sealed in a frame with the interior spaces filled with inert gas such as argon. A single-pane window has an R-value of 1.0 but the best high tech glass has an R-value exceeding 8.0 and therefore loses an eighth as much energy. (2)

holes : the opposite of an electron. In the Alice in Wonderland world of subatomic physics, the idea of a hole is required to explain the way electrons wander around in a semiconductive or conductive material. If the electrons wander from negative toward positive, then the holes meander from positive toward negative -- or else the law of conservation is violated. (3)

Holocene : the geologic age we inhabit, an incomparably clement period of time on our planet. (8, 14)

HUD : the federal Department of Housing and Urban Development, the agency that oversees the quality of American housing. (1)

hundredth monkey : (see 100th Monkey)

HVAC : the architects' shorthand term for Heating, Ventilation And Cooling. (4)

hydraulic ram : a simple device that uses the "water hammer" effect of a large vibrating column of water to pump a small amount of water up-hill surprisingly large distances. (1)

HydraulicRam.gif - 10165 Bytes

hydrometer : literally, "water measurer", used to measure the amount of water in a denser liquid, such as battery electrolyte (or beer). (4)

hydronic floor : a floor mass, typically of concrete or tamped earth, with tubes through which heated fluid is pumped. The massive floor takes up the heat and gently radiates it upward into the room. This gentle form of heating is the most efficient method for maintaining comfortable space. (8)

hypocaust : the ancient Roman term for a floor, usually made of slabs of marble or similar stone, constructed with the flue from a wood fire under the floor. Heat from the smoke heated the floor. Ruins of hypocaust-heated buildings can be found in France and England. (8)

incandescent bulb : a typical light bulb, like the one above someone's head in a cartoon; any light bulb that makes its light by heating a filament to incandescense. Such bulbs create more heat than light, and consume about 80% of their energy making heat. The incandescent light bulb is one of the most inefficient devices we use. Use compact fluorescent bulbs instead! (1)

infiltration : definitely a cold war problem: they come creeping in through the glass, around the windows, through the walls, out of the outlets, wherever a crack or opening or bridge allows cold air to enter the heated home. Temporary measure may help -- caulk, door snakes, storm windows -- but only good design and craftsmanship when the home is being built really solves the problem for good. (2)

infra-red scanner : a modified video camera tuned to "see" in the infra-red spectrum so that it can make an image of the cold places where infiltration is taking place (from inside the house) or (from outside the house) hotspots where heat is escaping. (2)

infrastructure : a fancy word for the artifacts that are necessary to support civilization: streets and highways, reservoirs, water and sewage treatment facilities, water mains and sewers, powerlines of all sizes and their associated substations, switching, and generations facilities, all the communications towers and stations, railroads, canals, and so forth... (1)

insolation : let the sun shine in! This technical term describes sunshine on a spot, and is usually given in the context "an annual average of 4.5 hours of insolation" meaning that the place gets the equivalent of four and a half hours of unclouded sunshine per day averaged over a year. (2)

insulation : not to be confused with insolation; this term describes any material used to keep energy from getting away. The insulation on wire protects the wire from mechanical damage, and keeps the electricity from escaping to neighboring conductive objects like our hands. The insulation in roofs, walls, and floors keeps warmth in during winter and out during summer. Both kinds of insulation share a single characteristic: They are very resistant to the flow of energy. (1)

integral : meaning that multiple functions are married into a single unit. In the case of "integrated roofing" this means that the weather surface of the roof also serves as the carrier for PV material, so the roof sheds water in bad weather and harvests electricity on sunny days. (3)

interconnect : describes the way a stand-alone home energy system can use the grid for storage by selling surplus electricity and buying it when the domestic supply is inadequate. Other terms for this are grid-interactive, grid-intertie, and grid-connected. (2)

inverter : a device that converts DC electricity, as produced by PVs and stored in batteries, into AC house current, the kind used by most familiar household devices. (4)

Jacobs windmill : one of the early mass-produced windmills, much favored by remote farmers prior to rural electrification. (1)

James Bay : a large bay in Canada, at the southern extremity of a larger bay, Hudson, between Ontario and Quebec. Abundantly endowed with wild rivers, but like many other "unexploited resources" subject to speculators who want to tap the resource and become big electricity suppliers to urban Canada and the U.S.'s northeastern corridor. For conservationists, James Bay is a symbol of rampant greed and wastefulness; they say, "let's get efficient first." (5)

kilowatt : one thousand watts, a watt being an instantaneous measure of electrical power, according to Ohm's Law, the mathematical product of current and voltage, P=IV. Ten 100 watt lightbulbs burn a kilowatt of electricity. (2)

kiva : a Navajo ceremonial round house built partially below ground, with a bench and niches around the outside for venerated objects and celebrants. (8)

lacunae : lapses (14)

latillas : the smaller straight branches placed between the vigas (rafters) to support indigenous Southwestern U.S. roofs. (8)

Laughlin-type soil : a very poor soil almost completely devoid of nutrients. (11)

lead-acid batteries : the commonest and most cost-effective form of storage batteries, found in vehicles, uninterruptible power supplies, and renewably powered home systems. (1)

learning curve : a awy of describing how easy or difficult it is for someone to learn a skill. If the learning curve is gradual, it's easy to negotiate, but very demanding skills like operating a nuclear power plant allow no room for error, and so the curve looks more like a wall. As industry moves along the learning curve of manufacturing a product, efficiency increases and cost decreases -- look what happened to calculators in the early 1970s. (16)

lineal foot : the unit of sale for objects usually delivered in long pieces, like pipe or 2-by-4. (8)

load center : once called the fuse box, this is where the energy is distributed via the bus bar and circuit breakers to various circuits. (4)

load : in electricity, any device that consumes electricity, so an electric water heater is a big load, and a clock or a night light is a little load. (2)

long-handled riding equipment : brooms. As a teenager, one of my chores was sweeping the 82 steps from the street to my house. One Saturday I was sweeping too hastily, and broke the brand new broom. My petite and very dignified mother accepted my explanation that it "just broke" and took it back to Mr Walker at the hardware store, who gave her another broom but added the admonition, "Madam, if you're going to ride it, you really should get the heavier model." (2)

low-e windows : one form of high tech glass, these are notable for their low emissivity, which means they incorporate a coating or plastic film that reduces the passage of radiant energy. (1)

low-voltage : in electrical terms, less than house current, typically 12 or 24 volts. (2)

Luddites : the disciples of Ned Ludd broke machinery and blocked access to factories at the start of the Industrial Revolution; since then, anyone who opposed industrialization has been called a Luddite or neo-Luddite. (4)

lumens : an exact measure of quantity of light. A 60-watt incandescent lightbulb and an 18-watt compact fluorescent light bulb each produce about 1,000 lumens. (1)

madronas : handsome and much-loved trees common in California and the Southwest, a member of the Heath family (Ericaceae), genus Arbutus. (13)

manometer : an instrument for measuring the pressure in pressurized systems such as ammonia-based refrigerators. (9)

marginal ... cost : Don't you just love it when Amory talks dirty like that? He means the additional cost of the improved energy system compared to the"base case" conventional way of doing things reckoned over a reasonable lifetime. (16)

micro-hydro : very small -- household scale -- hydroelectric generation, typically a two-inch "penstock" delivering water with a head of a hundred feet or less to a turbine the size of half a grapefruit connected to a modified automobile alternator; such a rig can easily keep a household in electrons day and night. (3)

micro-PV : small self-contained PV-energized devices like calculators, walkway lights, street numbers, emergency roadside call-boxes... (4)

million solar roofs : a political slogan put forward by a presidency attempting to mask its failure to deliver on its environmental promise, and as such a fairly typical federal program: lots of fanfare, and maybe even a little benefit. The idea was to have a million or more roofs in the U.S. helping with our electricity habit ...something that would have happened anyway. (3)

molecular assembly : bio-engineering techniques that assemble a product one molecule at a time, often using low energy under environmentally safe conditions. (1)

monetized costs : putting a dollar value on costs that have in the past gone unvalued -- for example, what is the dollar loss when a cultural site is inundated by a hydroelectric reservoir? (2)

movement : whenever two or three or more gather together to advance a shared agenda; the Back-to-the-Land Movement is an example. (1)

multicrystalline : many crystals of silicon in a semi-chaotic state, typical of medium-grade, medium-efficiency photovoltaic material; contrasts with high-grade, single-crystal, high-efficiency PV cells sliced from a single crystalline boule of purified silicon and low-efficiency thin-film amorphous modules. (3)

mutagenic : known to cause mutation (1)

n-type silicon : negatively-doped silicon (3)

negative charge : an object with a surplus of electrons is negatively charged; in our world, a single electron is the smallest negatively charged stable particle we need to think about. (2)

neo-Luddite, see Luddite (4,13)

net metering : an increasingly popular energy billing arrangement put forward state by state in which a small power producer, for example a renewably-energized home, can feed surplus power directly through the electric meter and into the grid, making the meter spin backwards, effectively using the grid as a 100% efficient storage device. The first edition of this book called for net-metering in 1993, and now almost half of U.S. electricity consumers have that opportunity; before that, two meters were required, and the utility paid only the "avoided cost", a fraction of the value for electricity generated by consumers. (2)

New Alchemy : a gathering of thinkers and doers who worked, among other things, on biological alternatives to chemical sewage treatment. (4)

nickel-iron batteries : same as Edison cells (1)

nominal voltage : the actual voltage of low-voltage energy systems varies widely during operation, but they usually hover above a basic, or theoretical voltage. A nominal 12 volt system would be in trouble at 11.8 volts, and fully charged at 13.8 volts; the energy sources -- PV, wind spinner, micro-hydro, AC-powered charger, or gen-set -- used to charge the batteries in such a system might produce 17 volts. Equipment meant for these systems must tolerate such fluctuations without grumbling. (2)

off-peak : times during which the demand for electricity from a system is not at its greatest, or peak. Peak demand is typically at 2:00 PM on a sunny week day, revealing bad architecture and overuse of air conditioning. (2)

off-peak hours : times definied by the utility as having the greatest system capacity (4)

oikos : the greek word for home, and the base of words beginning "eco-" (4)

one-line drawing : a diagram showing the logical and functional relationships between system components, but not all the connections or wires. A schematic drawing, by comparison, will show all wires, and so two connected components will often have two or more wires connecting them. (9)

operating cost : the cost of operating a system or appliance over its useful life. See "equipment cost" for a discussion of the relationship between these costs. (1)

order of magnitude : ten times; a dollar is an order of magnitude more valuable than a dime. This comes from scientific notation, in which a dime is 101 pennies and a dollar is 102 pennies, and provides a convenient way to discuss the relationships between large numbers. (3)

over-voltage : a circumstance in which the voltage is too high -- sun shining on a PV array on a cold day with snow on the ground might produce more voltage than a charge controller can handle, and so the over-voltage protection cuts the connection. (4)

overcurrent protection : a mechanism or circuit that protects a system from too much current -- the washing machine running at the same time a circular saw starts up will most likely trip the overcurrent protection of a small inverter. (4)

p-type silicon : positively doped silicon (3)

pathetic fallacy : attributing human traits and feelings to animals, objects, and devices. "The laser printer wants to see a 170 peak volts..." (1)

pathogens : materials which cause illness (1)

payback : when comparing two systems, usually a conventional low-price, high-maintenance system with a more expensive-to-buy but cheaper-to-operate system, payback is the time it takes for the total of equipment and operating costs of the more efficient unit to fall below the total for the conventional unit. (2)

pelton wheel : a turbine designed by an engineer -- guess his name -- to be driven by energetic streams of fluid issuing from one or more nozzles. The cups of the turbine are designed so that the water splatters clear of the stream from the nozzle after transferring a maximal amount of energy to the spinning wheel. (3)

penstock : the pipe leading from the forebay and headrace to the generator in a hydroelectric power plant. (3)

performance-based rebate : the idea that a professional's compensation might include an ongoing bonus for designing systems that save serious operating money. Such a rational feedback loop rewards professional excellence and punishes incompetence, and so is (of course) hotly opposed by professional organizations. (16)

permaculture : landscape design and plantings with the intention of having them last more or less permanently. The best way is to restore whole natural living systems using flora native to the habitat. (13)

PG&E : Pacific Gas and Electric, a large California utility that has pioneered wind and geothermal power sources, rewards for efficiency, grid-interties, and enlightened employee relations. (11)

phantom loads : small "convenience" appliances like calculators, lighted-dial phones, clocks, and so forth; individually they use tiny amounts of power but in a fully-accessorized household, their total load is considerable. (2)

PhD : post hole digger

photon : another mystical beastie, this time a "packet" of light, but something no one has ever isolated, described, or measured individually in any way. Since the "wave theory" of light is unable to explain the way light travels across the vast vacuum of space, a "particle theory" became necessary. It has proved a useful model, as it also explains the way the photoelectric effect works. Physicists find it very convenient to be able to switch back and forth between models when explaining the way light works. Some day they may find a unifying theory. Meanwhile, light is a wave, or a photon, depending... (3)

photovoltaics : shorthand term for photovoltaic modules. Those of us who know them well call them PVs. (1)

piezo-electric ignition : a mechanism for lighting as burner on a stove or oven that takes advantage of the piezo-electric effect, in which certain materials when struck by small spring-loaded hammer give off a spark. (9)

pioneer species : a plant or animal that tolerates harsh conditions and can grow on disturbed soil. Fire-weed is a classic example: after a forest fire, they grow up first, and shelter the later seedlings that will reconstitute the forest. (1)

PMS : Perpetual Midnight Syndrome, or the flashing 12:00 one sees on VCRs and other electronic clocks that lose their sense of time when the power fails, and whose owners don't bother to reset them. Evidence of a power thief in the act. (4)

pole barn : a barn built by attaching planks or boards to upright poles set in post-holes in the ground. You need a PhD (which see). (1)

potential : in electricity, the difference in voltage between two points in a circuit. The difference in potential between the poles of a golf-cart battery may be as much as 6.8 volts. The battery has the potential of delivering energy at something like that voltage. One never knows how deep the potential goes until it becomes kinetic. (4)

power center : an all-in-one control and load center which integrates several balance-of-system functions in one big box. A typical power center might contain one or more charge controllers, metering, and over-current protection (in the form of circuit breakers) for branch circuits. (12)

power cubes : power thieves that are always on and always using energy even when the equipment they power is off. Many phantom loads are fitted with power cubes. A typical power cube converts household current (nominally 117 volts AC) into low-voltage DC at an efficiency of something like 50%, with most of the waste being given off as heat. (2)

power-conditioning : the process of "cleaning up" the power coming from a dirty source, such as a gen-set or the grid, so that the spikes and brown-outs will not damage sensitive equipment. (3)

precession : the way a top's axle wobbles before it stops spinning. The same phenomenon explains the 46-degree "wobble" that governs the earth's seasons ... and no, the earth won't stop spinning anytime soon. (14)

public power : where the electricity is delivered by a publicly owned entity (5)

PURPA : Public Utility Regulatory Policies Act of 1978 (3)

putrescibles : things like meat and fish that rot and attract vermin before they compost (12)

PV(s) : shorthand for photovoltaic module(s)

PV array : a group of PVs wired to work together

PV system : a stand-alone electrical system in which the majority of the energy is harvested by photovoltaic modules. (1)

PV-direct : a system in which the load is directly powered by a PV array without any storage or back-up. A PV-direct pump is a good example. (2)

R-value : a measure of a material's resistance to thermal transfer (2)

radiation : a means by which a quality is carried across a medium without interacting with the medium; light reaches us from the sun across the vacuum of space.

radon : a radioactive (and therefore carcinogenic and mutagenic) gas (7)

rare earth : uncommon metals used for doping semiconductors and fabricating specialized alloys, including magnets. Rare earths include Cerium (Ce), Dyprosium (Dy), Gandolinium (Gd), Lanthanum (La), Praseodymium (Pr), Neodymium (Nd), Samarium (Sm), Terbium (Tb), and Ytterbium (Yb). (3)

rate : when buying energy, the cost per unit; in electricity, the cost per kilowatt-hour. Often utilities mask the true cost by separating out a metering cost, transmission costs, and other obfuscations, but the true cost is the total dollars paid divided by the total number of kilowatt-hours consumed. (2)

rate structures : tariffs or other tables that determine how much different classes of consumers pay for different amounts of electricity. A typical rate structure will have the aluminum plant consuming gigawatt-hours paying an order of magnitude less for a kilowatt-hour than the little old widow down the street. (2)

rectify : literally, "turn it right side up" -- and so, rectifying AC electricity (which varies from +170 volts to -170 volts 60 times each second) means changing it so it no longer alternates, but always yields a positive potential. A typical power cube steps the voltage down to twelve volts AC and then rectifies and conditions it to12 volts DC. (2)

referred costs : costs incurred for one purpose but paid for by others, often unwillingly. "For insurance reasons" highway contractors have taken to the use (and abuse) of flaggers who are hired to stop traffic so that a dozen men in orange coveralls can lean safely on their shovels in the roadway. The cost of the highway "improvement" never reckons the cost of lost hours referred to and absorbed by the folks sitting and steaming while they wait for the flagger to let them pass. (1)

resistive loads : electrical devices that do their work with heating elements, such as electric stoves, hot plates, heaters, and hair-fryers. In most cases, these are inappropriate uses of electricity in an independent home. (4)

retail therapy : making yourself feel better by going to the mall and buying things you don't need (12)

root mean square (RMS) : the mathematical calculation determining that AC electricity, which fluctuates periodically from +170 volts to -170 volts, is really 117-volt house current. To employ the pathetic fallacy, an appliance doesn't see the rapid fluctuations, but sees instead the energy effect of a steady flow of current. (2)

Ross Burkhardt : designer of the Burkhardt turbine (a micro-hydro generator), an expert solar installer, and more lately a zealous advocate of straw bale construction; a renaissance kind of guy. (13)

Rural Electrification Administration : the federal agency responsible for stringing the wires to remote farmsteads during the 1930s "recovery". (1)

safety disconnect : a switch that allows sources of power such as PVs and batteries to be disconnected from household circuits and control components so that they may be worked on safely. (4)

sanitarian : an expert in maintaining public health, particularly with respect to the proper disposal of black water. (1)

self-sufficient : in the extreme case, a system that is wholly reliant on its own abilities to gather its necessities within its own boundaries. In practice, an independent home may be self-sufficient in one or more specific areas -- electricity, heating fuel, and possibly building materials. Complete self-sufficiency is a major challenge. (1)

semi-conductor : a material that is electrically conductive under some circumstances, and resistant under others. Silicon, the basis of so many of our conveniences from solid-state electronic devices to PVs, is a semi-conductor. (3)

septictank.gif - 15928 Bytes septic tank : the typical rural destination for blackwater and most greywater. A septic tank is a cement or plastic tank holding a thousand gallons more or less for each bathroom, fitted with baffles so that the aerobic and anaerobic decay process that takes place and reduces the solid material to sludge which sinks to the bottom of the tank, the floating material is kept inside the tank, and the effluent, which is fairly sterile, flows out into a leach field where soil bacteria takes care of any pathogens before the water returns to the water table. In some areas, such as the Tahoe Basin, where rural development is reaching groundwater saturation, septic tanks are being phased out, and alternative systems are being evaluated. (1)

service-entrance panel : the electrical apparatus between the service drop and the household system. Usually the electric meter is located here. (16)

setpoints : in an electrical system, the parameters that govern how a component performs. Setpoints in a charge controller determine the high voltage at which the controller stops sending energy to the batteries, and the low voltage at which it starts charging them again. (16)

silicon : a semi-conductor (3)

silicon lattice : the orderly arrangement of silicon atoms in crystalline silicon (3)

single-glazed windows : windows covered with a single pane of glass (2)

sinewave.gif - 2404 Bytes sinusoidally : varying as the sine wave, sinuously (2)

skid-mounted PV systems : a home-energy system mounted on a portable platform that fits onto a trailer or in the bed of a pick-up truck, so that the system provider can assemble or service the system in the shop, then drive to the job site, skid the system onto the ground, plug it in, and away you go! (16)

social costs : typically referred costs or unmonetized externalities that enable a profiteering enterprise to enjoy profits and let society clean up after. A good example of social costs can be seen in the cost of administering health care to damaged smokers while the tobacco industry laughs all the way to the bank. (1)

solar assist : using the sun's energy to help a process along. Solar water heaters provide only a portion of the heat desired, so they give domestic hot water systems a solar assist. (1)

solar oven : an insulated box designed to capture and hold the sun's heat and use it for cooking. A home-made solar oven can easily maintain oven temperatures in excess of 400F. (1)

solar panels : any flat surface meant to gather solar energy, usually by converting sunshine into hot water. The term is also used (inexactly) to describe PV modules. (1)

solar window : the opening between trees, buildings, and other obstructions through which the sun can shine on a given spot.

southern exposure : the side of a house with the best exposure to the sun. (1)

specific gravity : the measure of the density of a liquid, with water defined as 1.0 (4)

specific heat : the measure of a material's ability to retain heat. Wood has very poor specific heat, while masonry, concrete, and rock are good. (2)

step-down : to reduce the voltage potential by directing the electricity through a transformer. A power cube typically contains a step-down transformer that reduces the house current to 12 volts. On the utility scale, large step-down transformers reduce high voltage from kilovolt transmission lines to lower voltage distribution lines, where other smaller step-down transformers -- the cans hanging on power poles -- reduce distribution voltage to house current. (16)

stick-building : condescending term for buildings made with 2-by lumber (16)

sticker price : the price on the sticker in the rear window of a new car, or, by extension, the equipment cost of any large-ticket item. (1)

sticker shock : the visceral response gotten when the sticker price is viewed, and a great motivator to purchase the less-expensive-to-buy, costlier-to-own item. (2)

stranded costs : bad investments made by utilities, especially in uneconomic or prematurely decommissioned nuclear power plants. In many states, one of the unheralded meanings of deregulation was that the consumers bailed out the utilities (thereby saving their stockholders a bundle) for their bad investments. Wouldn't it be nice if we could all arrange such a good deal with the ratepayers? (3)

strategic : of resources, meaning (1) that they might have value during an armed conflict, and (2) that we Americans are willing to send our young to war to protect our global right to plunder these resources. (3)

sub-atomic theory : an ever changing and ever-more-fanciful collection of theories about the composition and behavior of the constituents of atoms. Presently, quarks and bozons are the rage; quarks come in flavors, including Up, Down, and Strange. This is Big $cience at its most expensive, so don't laugh. (2)

sub-transmission : of utilities, one step down from long distance transmission. Long-distance very high voltage transmission lines carry electricity from generation facility to the outskirts of the city, where it is stepped down and carried by sub-transmission lines to sub-stations, where it is again stepped down to distribution voltages and along the streets. (16)

suns : of a concentrator, a mirrored or lensed array focusing brighter light on a PV cell: the equivalent brightness of a number of suns. A typical concentrator array will focus the light of ten suns on a cell. (9)

sustainability : the ability to keep on doing what we keep on doing. (various; 16)

swing season : the time between abundant sunshine and abundant rainfall or wind, generally spring or autumn. (3)

switch gear : the equipment used by utilities to change the configuration of the transmission and distribution lines. (16)

switched outlets : wall outlets wired so that they (and anything plugged into them) can be turned off with a wall switch. (4)

tailrace : the chaotic water just outside the hydro-electric generator, before the water calms down and enters the afterbay. (3)

teratogens : materials known to cause birth defects. (1)

terraform : originally coined by science fiction writers to describe the way a planet like Mars might be shaped to resemble Earth, but now used more generally to describe the process of making the landscape look the way a landscape architect thinks it ought to look. Sometimes, they're even right. (6)

thermocline : a sharp change in temperature between surface and deep water in the ocean; a particularly marked thermocline off the west coast of the Hawaii's Big Island (also called Hawaii) has been used experimentally to generate electricity. (3)

thermosiphon.gif - 7320 Bytes thermosiphon : plumbing that takes advantage of the fact that cold water is heavier than hot water (see convection), and will induce water to circulate as long as the heat differential is maintained. If a solar panel is placed below a storage tank, a thermosiphon will initiate itself, with colder water in the storage tank making its way into the panel, there to be heated and replaced by cold water. Gradually, this process heats all the water in the storage tank. (2)

Title 24 standards : guidelines promulgated by HUD to encourage builders hoping for federal government financing to implement minimal standards of energy efficiency. (16)

TJI : a constructed Truss / Joist I-beam built with an OSB web and plywood or 2-by-4 flanges (8)

tracker : a device that pivots on one or two axes to keep a PV array pointed squarely at the sun. Trackers can be passively aimed by captive CFCs or actively driven by actuator motors under the control of photocells. A one-axis tracker follows the daily motion of the sun; a two-axis tracker also follows the sun's seasonal motion. A tracker can improve PV yield by about 30%, depending on season and latitude, and usually costs about 30% of the value of the modules it tracks, so in many cases it is more cost-effective to buy 30% more modules and firmly affix them to a well-oriented surface. (1)

troglodytes : cave-dwellers, or, jokingly, people who are so happy on their independent homesteads that they seldom come to town. (1)

true cost : the whole cost, including exploration, exploitation, habitat restoration, transportation, refinement, disposal of impurities, packaging, distribution, advertising and sales, purchase price, installation, operation and maintenance, decommissioning, and recycling costs. The sticker price often neglects to mention some of the costs that should be included in the purchase price, and our decisions to buy seldom takes these costs or the differential cost to operate into account. When we do consider them, we usually buy more wisely. Critics of "true cost accounting" argue that some of these costs are difficult to monetize accurately, and therefore should be ignored. If you like that way of thinking, they also have a nice bridge they'd like you to buy. (1)

turbine : a wheel with vanes or cups on it designed to transfer energy from an energetic stream of gas or liquid to rotational energy at its axle. (3)

turbine generator : a turbine with its axle connected to a generator so that the stream of gas or liquid spins the generator and induces a flow of electrons. (3)

under-voltage : a condition where the potential is inadequate to power equipment, and may damage it. "Brown-outs" are forms of under-voltage caused by excessive demands on a utility's resources. In a home system or in a utility system, controls are installed to turn the power off when it is sufficiently under-voltage. (4)

unlumping : separating a random collection, such as household garbage, into its constituents, some or all of which may be recyclable. (12)

unmonetized externalities : costs that can easily be ignored, such as the known carcinogenic effects of diesel exhaust, because they are not directly borne by the immediate user, but by the tolerant and largely unaware society at large.

urban assault vehicles : officially known as SUVs or Sport Utility Vehicles, and much admired by the hip wannabe off-road set. Industry studies show that more than 80% of these vehicles NEVER leave the pavement, except when they crash, which they do with distressing frequency. Proud owners invariably cite a special need, like "I need it when we go skiing". The auto industry also loves them because they are trendy, highly marked up, easy to build, and expensive to maintain. (2)

utility-interactive : another term for a renewably energized system that stores surplus power in the grid. (2)

utility-scale : large and complex electricity generation and distribution schemes serving a large community, as a contrast to simpler home-scale or neighborhood-scale power systems. (3)

UV (Ultraviolet) : the fraction of sunlight known to be carcinogenic (9)

valence band : the outer "shell" or region of reactive electrons in an atom. Electrically conductive elements have many electrons in their valence bands, while insulators have very few; semiconductors, as you might expect, fall in between. (3)

variable selectivity window : a window with a special film on it which changes reflectivity depending on electrical signals. Think of it as venetian blinds on a molecular level. (16)

VDT : video display terminal, the device most folks look at while doing their computer work. (4)

Vietnam experience : an unsettling period in global history during which massive military strength and willingness to sacrifice brave young men proved to be insufficient to defeat an entrenched and committed native people even as it destroyed the local biosphere and many tens of thousands of lives. It changed us all. (1)

vigas : larger straight round rafters on top of which the roofs of adobe homes are constructed (8)

watercourse : the place where water runs, if there is any water (3)

watt : a measure of electrical power, calculated as the mathematical product of voltages times amperage. A 5 watt 12 volt halogen light -- a typical low voltage walkway light -- consumes about four tenths of an amp. (2)

weather-stripping : usually metal-reinforced felt gaskets or seals that reduce infiltration around windows and doors. (2)

whole cost : another term for true cost, which see. (1)

whole-house fan : a powerful fan capable of changing all the air in a house several times an hour. Whole-house fans are used instead of air conditioning in climates where it is warm by day and cooler by night. During the evening hours, the whole house fan circulates cooler air through the house, charging its thermal masses with coolness. By day, the house is closed up tight, and the thermal masses "radiate coolth" and keep the indoor temperatures bearable. (2)

windcharger : another name for windspinner or wind generator: a propeller connected to a generator (3)

windmill : a wind-driven turbine used to perform a mechanical task such as pumping water. Windmills usually spin more slowly than windspinners. (1, 3)

worm-drive saw : a serious carpentry tool, admired by serious carpenters. Because the axis of the motor is parallel to the blade, the tool doesn't jump (as much) when it's turned on. (12)

xerophytes : plants, usually natives, that do not require watering to make it through a dry summer.

yurt : a round portable building made of felt


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