 For a while the photovoltaic panel - electricity from the sun - was quite an attractive cause for politicians. In the UK the EST would give out grants usually for half the cost of an installation. A good 1.5kWph installation might cost around £9000 to install but the British Government then gave you £4500 back in grant money - usually paid straight to the installer who filled the forms in for you.
However, in 2007 the sun temporarily set on the industry as the Government cooled its enthusiasm. Grants under the Low Carbon Building program were capped at £2500 per household - and that is IF you can get them. The scheme had already suffered long delays in getting its monthly funding from Government coffers leading to long waits for many applicants. Why the change? No, it has nothing to with the lack of Sun - in fact we have loads of Sun - more than enough to make Photovoltaics work very nicely! (Potentially 30 TWh annually alone in the UK.) No, but it is an absurdly expensive way to save carbon. It is bottom of the list after bio-mass, wind-turbines, nuclear, carbon capture on coal power stations, and so on. However, conventional economics tend to tell only half the story. Indeed, Photovoltaics seem very expensive in comparison to Fossil Fuels. However, Oil prices do not include the cost of replacement technology nor the potential cost of disposing of its waste products. Unlike all the alternatives Photovoltaics has one massive advantage. Whereas few of us will ever own a wind-turbine or be able to grow energy crops, practically EVERYONE can participate in Solar Power. Expensive as they may be, you can bolt those solar panels to any building and their capital cost is far lower than the smallest Nuclear or Coal Power station.  Unlike Wind or Wave Power you can cover a modern building with photovoltaic panels and it will be cheaper than other expensive prestige coverings. The Industry just needed to achieve market penetration. Mass production was needed to decrease the cost. Photovoltaic panels needed to be produced in every shape and size. They needed to be direct substitutes for normal building coverings. Such devices already existed - the "Solar Tile" had been on the market for several years but suffered from being 1.8 times the cost and 5% LESS efficient than regular 'bolt-on' systems. Semi integrated systems were a good compromise at 1.3 times the cost. Hybrid systems are now available that combine Solar Electric with Solar Thermal - electricity and hot water (picture below)! So there were plenty of good ideas and new options appearing all the time. It is also believed that, with the march of technology, the cost of photovoltaic cells could rapidly fall. We hoped so.
Take one case study: When combined with Energy Saving Light bulbs a three bedroom house in the south of England went from consuming over 4400 Units of electricity per year in 2004 down to just 2500 (a drop of 42%) after installation of 1.5kWph unit in 2005. This household was earning over £70 a year from its exported electricity. This was enough money to pay for another three months worth of electricity. In essence this house got 7 months worth of free electricity every year. The per person annual Carbon footprint of this house's occupants dropped to 2.2 tonnes whereas the UK average was 5.4 tonnes. 
However, even in 2005, you would never make your money back but it still made a big difference. If every householder did it (or the panels were simply built into every new home) then they would quickly contribute 10% of our Power needs within the United Kingdom. This is a very conservative estimate. You could actually produce over 200 terra-watt hours (TWh) per year just from the sunlight falling on rooftops in the UK. The UK only needs 400 TWh per year! That is 50% just from rooftops. That doesn't account for anything like the total available landmass. So much solar radiation reaches the ground that all of our energy needs could be met many thousand times over with a simple piece of technology with no moving parts. How wonderful is that? Very wonderful in fact. So wonderful that by 2008 the Climate Change Bill was passed in Parliament. With it came a new Energy Act that introduced the Feed-in Tariff. The so called "clean energy cashback". The Feed-in Tariff is modeled upon a scheme operating successfully in Germany for many years. Its intention is to boost the use of domestic renewable energy, hence it will boost the sector, 'kick-start' the industry in the UK and create green jobs.  From 1st April 2010 householders and communities who install low carbon electricity technology such as solar photovoltaic (pv) panels and wind turbines up to 5 megawatts will be paid for the electricity they generate, even if they use it themselves. The level of payment depends on the technology and is linked to inflation. It is tax free too. They will get a further payment for any electricity they feed into the grid. These payments will be in addition to benefiting from reduced bills as they reduce the need to buy electricity.
The scheme will also apply to installations commissioned since July 2008 when the policy was announced. A typical 2.5kW well sited solar pv installation could offer a homeowner a reward of up to £900 and save them £140 a year on their electricity bill. Ofgem will administer the feed-in tariff scheme and suppliers will be responsible to paying the reward to their customers. The electricity supplier pays the Feed-in Tariffs (and bills users for the electricity imported in the normal way). Suppliers may choose to 'net these amounts off' and just pay a cheque or submit a bill for the difference. Claimants can appoint an agent to collect the tariffs on their behalf. Meters will be needed to measure each of the three energy flows (generation, import and export). You will already have an import meter, and the others may be similar - though the whole country is changing over to Smart Meters in the next few years, and they will be able to cope with all this. The UK currently gets around 5.5% of electricity from renewable sources and that will need to increase to around 30% to meet the 15% 2020 target for all energy. Modeling show that small scale renewable installations could meet 2% of electricity demand in 2020. The UK currently gets less than 1% of heat from renewable sources. This this will need to rise to around 12% in order to meet the 15% 2020 target for all energy. There are a couple of good web sites you can check out if you wish for further information. These are: - www.fitariffs.co.uk - www.ownergy.co.uk Investors in Photovoltaics will be largely insulated from price rises that Ofgem warn could see household bills reach £2,000 pa by 2020. A typical 2.5kW well sited Photovoltaic installation could reward a homeowner with up to £900 per year and save them £140 a year off their electricity bill. Householders making this investment will get a further payment for any electricity they feed into the grid. Could you say that about a new car or fitted kitchen? Don't be deterred by the idea that the UK doesn't get enough sunshine - the sun here is more reliable than you think and only around one-third less powerful than that in southern Spain. The technology can work on south-east or south-west facing roofs too. Most of the electricity generated is consumed by the householder so virtually no energy is lost in transmission. More distant power stations can lose over a third of their energy generated in such a way. For an example of all this working trip over to our post-carbon homes section and see the 3kWp system installed there. We will hopefully be getting our first FiT payments in 2010. | 
