The starting point

It's been on my mind for decades that I would like to use the power of the Sun to generate electricity and now the opportunity has arrived. I'm going to blog my progress and see how it goes.

When I looked into it seriously in 2000, I was put off by the payback time. I remember electricity was about 7 pence per unit. When I worked it out, it seemed like it would take 120 years; 60 years when I took the then available 50% government grant into account. Now the situation has changed markedly. There are still grants available and politicians are falling over themselves to offer interest-free loans. Best of all, from 1 April 2010, a new system of reward for the microgeneration of electricity will come into operation - the Feed-in Tariff, or FiT.

As I understand it, FiT works like this. For every unit of electricity I generate, I will get 41.3 pence of tax-free income. This will be guaranteed for 25 years and will be linked to the RPI. If I use that electricity, then that is power I won't have to buy from the grid, saving me 11 pence per unit. Finally, if the system is generating power and I can't use it, I'll get a further 3 to 5 pence (depending on who you listen to) for exporting it. This completely changes the economics.

On a cold but sunny winter's day in late February, I visited a house where they have a large system. The owner proudly informed me he had generated over 15 units that day as the Sun was setting. That house had a 3.5 kWp solar photovoltaic array on its roof. I was getting interested in this.

There are a large number of hoops you have to jump through to take advantage of the grants and loans available for microgeneration and I'll try to relate here how I pick through them. First of all, there are grants of 30% up to a max of £4,000 available here in Scotland. [Later note: These grants were discontinued before I got to take advantage of them.] There are interest-free loans of up to £10,000 available but apparently the funds for these are nearly exhausted. [Later note: Maximum loans have been reduced to £4,000.] All this government largesse is only given if the powers-that-be are satisfied that you have implemented appropriate energy saving measures in your home. After all, the point of this intervention and incentive is to reduce the UK's emission of carbon. I think a discussion of that will be for a future blog entry.

The 41.3-pence FiT is only available on solar PV systems that have been retro-fitted onto existing houses and only up to a maximum of 4 kWp. Other rates apply for other sizes and other technologies for the microgeneration of power. OK. I would get a system that was slightly smaller than that. The 3.5-kWp system I had seen cost £14,000. It seemed I could get a grant of £4,000 and a loan for essentially the rest. OK. So what's first? I have to get a report from Energy Saving Scotland to check that I have mostly low-energy lightbulbs, have insulated my walls and attic and that my radiators are fitted with thermostatic valves. I do, I have and they do. I'm now awaiting a report arriving in the post that will clear the way for an application for a grant and a loan.

Meantime, I have got a quote for the system. 20 panels, each capable of 175 W peak and it's a shade over £14k. I've even used photoshop to simulate what they would look like on my rear roof. This is cool!