Distributed energy systems:
conservation and
micro-generation

briefing document

site map

index
introduction
    basic facts of long distance electricity transmission
    energy micro-generation
local approaches to energy independence
    do it yourself power generation in california
conservation
bibliography
end notes

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disclaimer

Almost all present energy systems are centralised and in the control of big corporations and big governments. The future of energy production will probably involve local community and individual household generation, that is distributed energy systems. This is not an either/or situation. Systems will be range from very large central distribution to very local systems for personal use and efficiency. That is, ranging from a big power station to draught-excluding your front door.

Energy is is involved in all human activity and production at every level and at every stage. It is essential not to miss this and think on terms of single issue fixes.

A very major part of future energy concerns will be conservation.

What you conserve, you do not have to generate.

There are further background documents listed in the sustainable futures briefing documents.

basic facts of long distance electricity transmission

“The most cost-effective way to generate large amounts of electricity is with a rotating synchronous generator, which naturally produces alternating current. ” [Quoted from http://www.transpower.co.nz - page unavailable]
—
On high-voltage direct current transmission [HVDC]:
“While it is expensive to convert normal AC power to DC power and back again, the savings in power losses and in construction costs can make HVDC cost-effective if moving more than 500 MW further than about 500 km over a point-to-point link.”[Quoted from transpower.co.nz]

HVDC electrical losses are about five percent per thousand miles.

energy micro-generation

“There are striking parallels between the renewable energy industry today and the personal computing industry circa 1980. Much of the basic technology required for personal computing was already in place and was on the verge of becoming economical for mass production. The personal computer hardware and software industry was characterized at that time by small, under-capitalized firms that catered to a hobbyist market (known today as "early adopters," in industry parlance). The software and hardware of that time was more complicated to install and use (early computers were generally useless except to programmers).”

on economic barriers to replacing fossil fuels

Commentary: the fossil fuel producers will do whatever possible to stop alternate energy becoming a serious competitor. Currently oil is very cheap to produce, despite the horrific levels of pollution pumped into the air and the rapid depletion of a vital resource. Only by heavily increasing taxes on these externalised costs can fossil fuels be made less attractive. This will of course be resisted by corporations and the Middle East dictators. This would still be insufficient if some countries are allowed to go on exporting their pollution filth.

It is cheap oil that is at the core of enabling the major wars for the last century to be fought. If Western societies forgo cheap oil, then is highly likely that others will see oil as a means for conquest. Such is the tragedy of the commons represented by cheap fossil fuels, especially pumpable oil.

It is not sufficient, as the writer in the above-linked article appears to believe, that merely making alternative energy competitive on price with current fossil fuel prices would work much to replace the oil. The oil interests would merely drop the price below current alternatives.

local approaches to energy independence

moving to sustainable local energy generation

• photo-voltaic

“Technological improvements have made solar-electric modules more cost-effective. In the 1980s the average price of energy captured with photovoltaics was 95 U.S. cents per kilowatt-hour. Today that price has dropped to around 20 cents per kilowatt-hour, according to Collins, of the American Solar Energy Society.”

In developed countries, solar-generated electricity is four times more expensive than ‘brown’ electricity made with coal and gas, with the solar panels having a 20-30 year lifespan. [2006]

• solar panels

“In the last two decades solar-thermal panels (units used to warm household hot water, pools, and spas) have become highly efficient. Energy costs have decreased from 60 cents to 8 cents per kilowatt-hour since the 1980s, Collins said.”

• wind generation

  “Compared to other renewable energy sources, wind power competes with conventional energy at a price less than 4 cents per kilowatt-hour, Collins said. ”

• ground heat pumps

  “Ground-source heat pumps, also called geo-exchange systems, use this relatively constant temperature to keep homes at comfortable temperatures.”
  Some systems are using underground water tanks, designed to heat up during the suimmer and release heat for household use during the winter.

thinking of working towards going off grid? - using wind for power generation at home

While the claims of this linked article are almost certainly accurate, and you should read the article and beware, encouraging a free market in local energy is positive and should gradually serve to make people more educated on the subject.

There’s nothing like paying for a device without first investigating the hidden details to make people more alert and cautious next time around, if it does not meet its claims.

Obviously, no government grant should be attracted by idiotic purchases, but of course it is old.new.old Labour government we have in the UK.

“Windsave, which makes the turbine that will be sold by B&Q and will be selling directly via the internet from August, says its 1.75 metre turbine produces 1,000-2,000 kilowatt hours of electricity a year. Renewable Devices says its Swift 2 metre turbine produces between 2,000 and 3,000 kwH of energy a year, and could save the householder up to £300 a year, including the value of green energy generation certificates.

“But Archibald says that low wind speeds in urban areas mean that most installations will never come near that. 'In better locations we'd expect wind speeds of six metres per second, but in urban areas, with lots of other buildings around, you're probably looking at four [metres per second], and that will affect performance considerably.'

“Nick Martin of the Hockerton Housing Project, a sustainable development in Nottinghamshire, is a construction expert who has monitored performance of much larger, pole-mounted turbines and investigated the claims of the rooftop turbine makers. He says that Swift and Windsave's performance claims 'defy the law of physics' and that they will produce much nearer to 10 per cent of the average household's energy needs.”

I am presently [late June 2006] investigating heat exchangers (the air type - there are also earth/buried units that are probably better to be built in during construction) which are claimed to provide approximately an extra third of heat relative to electricity usage. They are also said to be rather noisy. These heat exchangers will also cool you in summer, so you might end up paying bigger electricity bills over the whole year!
[See also Jevons’ paradox.]

Note that electricity energy substitution is in direct competition with large power stations, and that those power stations are very profitable. Methods used in the USA include making it profitable for power generation companies to help users to conserve power. This is particularly useful if a whole power station can be avoided by keeping the ‘demand’ under control.

do it yourself power generation in california
page 1 page 2

On the same site, there is an excellent worked example of do-it-yourself power generation for the home.
Note carefully the various subsidies and that this development is in sunny California.

It is also vital to note that this is replacement for home electricity use. It pays no attention to the energy used to manufacture the system (although the cost of the system could be used as a surrogate), but more important, there is no reference to the energy inputs for building the house, the variety of toys which may fill the house, the various foods consumed by the household and use of other services such as transport. Nor does the writer say how many people are living in the house, or make clear whether he was using means other than electricity for heating before he started this project.

You will see from the fuel usage efficiency table, column 7, that the average electricity consumption in the United States is 1.4181 kw-hr; that is 12,443 kw-hr per person per year [8760 x 1.4181]. Electricity consumption represents approximately one-third of the overall energy consumption per person in advanced Western societies [columns 2 and 3]. The writer, thus, is producing about 69% [8600 kw-hrs (1) in year / 12,443] of the electricity consumed by the average person in the USA; this is approximately 23% of the total energy used per person [and that is 1/3 x 69%].

This is doubtless a useful contribution, but would shrink further in percentage terms if there were more people living in the household, or if there was an SUV parked in the garage, or long-haul ’plane flights were a common part of the owner’s lifestyle.

conservation

Conservation is not some mere after-thought add-on, but a major potential contributor in obtaining improved outcomes to the pressures on fossil fuels and the environment.

When a product is cheap, there is a tendency to waste it. Savings of energy precludes you having to obtain and produce energy in the first place. Conservation is often possible at no net cost or even at negative net cost. Energy conservation not only saves the energy, but saves the energy required in producing the energy. As there is so much saving that can be obtained by better pre-planning and, often, fairly minor changes to behaviour, it is probable that very large amounts in equivalent big power station terms may be gained under the heading of ‘conservation’.

The onrush of knowledge and cost-benefit analyses (COBAs), make assessing the potential scale of conservation benefits difficult. One of the great lessons of modern technology has been to grasp that very great strides can be made by dint of a thousand small improvements, rather than necessarily with one giant leap.

David Pimentel, a world leading researcher in the energy field, has recently suggested that one third of energy in the USA could be saved:

pimentel claims america could cut energy use by cutting subsidies to big oil [press release]
(original report, [click on Issue 3, September 2004 to reach detail] costs $25 online or view at a good academic library)

“The next time you're pumping gas or paying the heating bill, ponder this: As high as fuel prices are in this country, they would be even higher without government subsidies to prop up the industry. Instead of paying at the pump, every American family is paying about $410 in taxes each year for subsidies that keep gasoline prices and other energy product prices artificially low. This policy encourages greater consumption and importation of more oil and natural gas. Ending subsidies and pricing energy at its true cost would stimulate the use of conservation and energy-efficient technologies, and result in net savings.”
—
“We are confident that the president and the U.S. Congress, working with the people, could reduce our energy consumption in approximately a decade by 32 quads (32,000,000,000,000,000 BTUs) per year, about 33 percent of present energy use. ”

The two books cited below can give you a feel for the considerable potential scale of conservation savings.

conservation standards in the usa

“In high-energy New York City, the Solaire is a building permanently on power-save mode. When final construction ends later this fall, the 27-story building, located just a few blocks from Ground Zero in lower Manhattan's Battery Park City, will stand as the world's most environmentally responsible residential high-rise.

“The Solaire will use 35 percent less energy than a conventional structure of similar size and purpose. At least 40 percent of its components were manufactured within 500 miles (800 kilometers) from the job site, which adds the benefit of reduced transportation pollution. Even building materials incorporate recycled content.”
—
“ "The general rule of thumb is that you can build a LEED-certified or silver rating building for the same or less first costs," said Ervin, who added that this is particularly true when LEED certification is approached early in planning. Ervin notes, however, that the higher a building is rated above the silver rating, the greater its development and construction cost.”

insulating an existing old house

Useful ideas for upgrading an old house to be more ecological, but these people do appear to have a lot of money to spend.

“With a low energy house it is important to maximise the use of the warmth of the sun so that it can help heat the house in the colder months. This principle is known as passive solar design. To maximise the retention of this heat it is necessary to 'trap' it by means of high levels of insulation and by minimising the amount of warm air that is lost to the outside. This principle, taken to its extreme, is known as superinsulation. When the sun's energy is used to make electricity or heat water this is known as active solar design. When a building's fabric is able to store heat when it is warm and then release it a few hours later when it becomes colder, this is known as thermal mass. It is these four basic principles which have been carefully combined in the retro fit of this house to drastically reduce the energy consumption, and hence the CO2 emissions.” [Quoted from msarch.co.uk]

ecohouse features at a glance - list and clearly marked cross-section of house.

Page describing the various parts of this ecohouse project in detail, including a long section on insulation - roof, walls, floor, external and interior.

conservation on a personal level

“"If every household in the United States replaced its next burned-out light bulb with a compact fluorescent," the authors say, "We would prevent more than 13 billion pounds of carbon dioxide being emitted—that's equivalent to taking 1.2 million cars off the road for an entire year."

“The annual amount of money saved as a result of replacing four incandescent bulbs with compact fluorescent bulbs, taking into account the initial cost of the new bulbs, is U.S. $30, according to the authors. Over the lifetime of the four bulbs the total saved would be U.S. $205”.

keeping the heat in during winter

Don’t pay to heat the universe:

• “United States Department of Energy (D.O.E.) statistics show that 44 percent of the average home's energy use is devoted to heating and cooling.”
• “Heat-loss through windows accounts for 10 to 25 percent of your home heating bill.”
• “Insulate. Priority one is the roof, where rising heat tries to escape your home. If you already have insulation, consider increasing the amount in your attic. "It's basically adding another blanket on your bed," Silva said. "But be sure you don't separate insulation layers with a vapor barrier. Also, it's very, very important that the more you insulate your attic, the more you must ventilate. The attic is a space that you don't want to heat. Ideally, you'd want the underside of the roof to be as cool as the outside.”
  [Quote from Bluejay]

some home energy conservation tips

electricity savings

• use energy-saving light bulbs (compact fluorescent bulbs)
• turn off lights when leaving the room
• buy a new fridge: old fridges are less energy efficient and may have damaged door seals
  - keep the condenser coil clean
  - wrap or cover foods and liquids in the fridge, thus stopping moisture release - moisture slows cooling
  - on freezers that are not frost-free, defrost the freezer before the frost exceeds a quarter-inch thick - more frost makes a freezer work harder
• using a microwave for cooking where possible could save up to 20% energy
  - food cut smaller cooks quicker
  - keep ovens and microwaves clean - the food will cook faster
  - ceramic or glass dishes in the oven hold heat better than metal ones
• laptop computers are up to 90% more energy efficient than desktops
• plug similar equipment (TV, DVD player, amplifier... ) into one power strip/plug batten and switch that off at night, to prevent trickle electricity losses
  - do not leave equipment on standby
  water heating
• turn down the water heater - 10°F less saves 5%of its energy use
• insulate the heater and hot water pipes
• drain a litre of water from the tank base every three months, preventing sediment build-up
• buy a new water heater if yours is more than 7 years old
  washing and drying
• using warm or cold water can halve energy use
• rinse clothes in cold water
• run washing machine with a full load (or use small load/low water setting)
• be economical with detergent - more suds need more washing and energy to wash them out
• dry washing outdoors on a washing line if possible for zero energy waste
• keep the dryer maintained - lint trap cleaned, exhaust hose unblocked
• always dry a full load
• dry heavy fabrics separately to lighter ones - so all items are dry at the same time
  dish-washing
• do not pre-rinse dishes before putting in dishwasher unless really necessary - scrape off bits
• always run dishwasher with a full load
• use energy saver setting if possible
• use air-dry option (recycles heat already present to dry dishes) or open door so dishes dry
• upgrade to a more energy and water efficient machine

related material
Replacements for fossil fuels—what can be done about it?
Sustainable manufacture

And quite a bit more interesting information, figures and conservation ideas.

bibliography

	You Can Prevent Global Warming (and Save Money!): 51 Easy Ways by Jeffrey Langholz and Kelly Turner Although very useful, this book has a reduced GoldenYak rating because many of the figures provided are unreliable.
	£6.27 (amazon.co.uk) / $8.76 (amazon.com) 2003, Andrews McMeel Publishing.,pbk, 0740733273

	Factor Four: Doubling Wealth, Halving Resource Use by von Weizsacker, Lovins and Lovins
	£12.95 (amazon.co.uk) 1998, Earthscan Publications Ltd., 1853834068

end notes

1. This is an estimate from the article as follows:
   5000 kw-hours solar panels, 1800 kw-hours water-heating solar panel (figures in the article)
   and a guesstimate of another 1800 kw-hours from the additional solar panels.

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© abelard, 2004, 22 december
v.1

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the address for this document is http://www.abelard.org/briefings/energy_solutions.php

2500 words
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