"Germany has already shown that such a system can work. There, homeowners selling back renewably generated power are guaranteed to get four times the market rate charged to consumers for electricity. As a result, Germany has a thriving market in domestically generated energy, with 200 times the solar electricity output of the UK."
"Perez, a renewable-energy researcher at the University at Albany, State University of New York, lives "off-grid" - unconnected to the power grid and the water, gas and sewerage supplies that most of us rely on. He generates his own electricity, sources his own water and manages his own waste disposal - and prefers it that way. "There are times when the grid blacks out," he says. "I like the security of having my own electricity company."
"For people who live off-grid, self-sufficiency means guilt-free energy consumption and peace of mind. "It feels brilliant to use clean, free energy that's not from fossil fuels," says Suzanne Galant, a writer who lives off-grid in rural Wales. "And if something goes wrong, we can fix it ourselves." Now even urbanites are seeing the appeal of generating some if not all of their own power needs. So is energy freedom an eco pipe-dream or the ultimate good life?"
"The biggest energy savings will come from properly insulating your home to minimise heat loss. That done, you'll need to work out what is eating up the rest of the power you consume. The easiest way to do this is to buy an energy monitor that can provide a live display of your total energy consumption or that of individual appliances (see "What's guzzling the juice?"). This will help you focus on reducing consumption to the bare minimum, not just by switching to low-energy light bulbs and energy-efficient white goods, but also by turning unused appliances right off rather than leaving them in standby mode. With a bit of effort and investment, you should be able to get by on a few hundred kilowatt-hours of electricity a year.
Now you are ready to start replacing this with home-grown energy. Some 80 per cent of off-gridders rely on the sun to do this, with good reason: it blasts our planet with enough free energy every hour to power the world for a year and you don't need to live in the middle of nowhere to get it. The simplest way to tap into this is to use a solar collector for your domestic heating or hot water. In the summer, solar thermal devices installed on a south-facing roof or wall (north-facing in the southern hemisphere) could provide all your hot-water needs. Even in winter, solar collectors can make a worthwhile dent in heating bills, even if the water needs top-up heating from the grid or from a stove that runs on logs, wood pellets or other biomass.
The sun blasts our planet with free energy and you don't need to live in the middle of nowhere to get it For electricity generation, photovoltaic (PV) solar panels are also a good option. They convert the sun's rays into direct-current electricity with up to 20 per cent efficiency, and most are guaranteed to retain at least 80 per cent of their original efficiency after 25 years. A 2-square-metre panel rated to give 1 kW per square metre in peak conditions could provide up to 1500 kWh per year in the UK. In more southerly and reliably sunny latitudes - somewhere like Texas, say - it would probably provide 2000 kWh per year.
With enough solar panels it is possible to cover all your electricity needs with PV, year round; the downside is that it requires a significant investment up front. Installing 8 square metres of PV panels, enough to sustain a family of four in the UK, plus storage batteries and accessories such as inverters to convert DC into alternating current, can cost tens of thousands of pounds and will take up more space than is available to most urban households. Until the cost comes down substantially, switching to a grid supplier that gets its energy from renewables may be a more realistic alternative - although it will not free you from the risk of supply interruptions."
"For most of us, the energy-storage issue is a major stumbling block to going completely off-grid. And it's one reason why, for most people, it's not yet worth pulling the plug. Cost is likely to be another show-stopper - though not for those who live in really remote locations. "If you live more than a quarter of a mile from the grid, then installing your own systems works out considerably cheaper than connecting to the grid," says Otto van Geet of the US National Renewable Energy Laboratory in Golden, Colorado. Perez, for example, was told it would cost him $280,000 to be connected, which made the decision to install $25,000-worth of PV panels an easy one. Both of these barriers are coming down, albeit slowly. Engineers are working on reducing the size and cost of renewable-energy installations, while fuel-cell and battery manufacturers are trying to increase power output and storage life. The cost of generating and storing your own energy will fall as the commercial and domestic generation market grows and as new technologies emerge: thin-film PV panels, for instance, are cheaper to make than existing PV cells, which use crystalline silicon. For many, the transition is becoming easier and less costly as newly built houses are increasingly offered for sale with some of the infrastructure for renewables, such as inverters for PV panels, already installed.
In the meantime, one way to beat the problem of how to store surplus power and make good on your investment is to stay connected to the grid - or connect if you are already off-grid - and sell what you don't use to a utility company. It may not be the energy freedom you had in mind, but it does means that the grid effectively becomes your battery - there when you need more electricity, and able to take your excess power. The return you will receive for this varies widely, but Germany has already shown that such a system can work. There, homeowners selling back renewably generated power are guaranteed to get four times the market rate charged to consumers for electricity. As a result, Germany has a thriving market in domestically generated energy, with 200 times the solar electricity output of the UK.
The UK is planning to bring in a similar "feed-in tariff" system in 2009, although it is not yet clear what sort of price power-generating homeowners can expect. In the US, California and New Jersey are leading the way with feed-in tariffs in the range of 8 to 31 cents per kWh, depending on the contract and the time of day when the power was generated. Most other states have a long way to go."
http://www.newscientist.com/article/mg20026851.600-how-to-unplug-from-the-grid.html?full=true
Rapport från Stanford: Elbilar bäst - E85 sämst
http://www.nyteknik.se/nyheter/fordon_motor/bilar/article515980.ece
Kärnkraft är dyrt och farligt
http://intheendwerealldebt.blogspot.com/2009/02/karnkraft-ar-dyrt-och-farligt.html
Avskaffa elproduktions monopolet
http://intheendwerealldebt.blogspot.com/2009/01/avskaffa-el-produktions-monopolet.html
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