Even when we moved into our house in Hazelbury Bryan in 1989 I knew I would one day put some photovoltaic panels on the roof. It’s a nice simple roof and near perfect south facing. In fact is southerly orientation is one of the main reasons we like the house. It always feels light and sunny (weather permitting.) However, my wife is very pragmatic, we’ve never been rich and the cost of the panels has been just too high. When I checked the first time in 1999 they had a 50 year pay back! So it was a no.
Then during a pleasant drunken session at my local pub one evening during 2010, I persuaded a fellow village mate that he could benefit from a career change to become a PV salesman because I reckoned (beware of people who reckon something!) that the new feed in tariff that the government were introducing would lead to massive growth of that industry. I have to admit to being very surprised to discover a few months later, that he had taken me seriously and had become very busy with what he described as “consultative salesmanship” at a series of home visits and surveys.
I felt obliged to allow him to quote for a 4 kW PV array on our roof. He told me he’d give me a good deal (as they do.) I got a couple of other quotes and “negotiated” a bit. Even my wife now thought the financials looked good. £15,000 for a 4 kW 16 panel top of the range (18% efficient) Sanyo system. The returns were estimated to be a total of £1.870 from the feed in tariff, lower electricity bills and electrical export to our electricity supplier from the 3,700 kWh our system was expected to generate. That’s an eight year payback and a 12.4% return in the first year!
We had various bits of savings, none of them earning more than 3.5 % after tax (and some a lot less!). So we bit the bullet and had the panels installed on 22nd June 2011. As of 18th April 2012 we have generated 3,240 kWh and received 2 cheques from our electricity supply company for the first 6 months totalling £943. We still have a bit of April, May and most of June to go before it will have been in for a year so I think we will comfortably exceed the predicted generation. I reckon (I do a lot of reckoning) that our end of year generation will be around 4,100 kWh. That will be worth £2,120 giving us a 14% return and a 7 year payback.
However, I was miffed to discover that if I purchased the same system today it would cost us just £8,000! But then you have probably heard that the government have dropped the tariff rate by half to 21p/kWh. That would be giving me a 14.9% return. So not much change. The good news for us is that once you have installed, your tariff rate goes up by inflation each year (for us it is 45.4p/kWh from 1st April 2012), so up goes the rate of return and down comes the payback period. Any increases in electricity prices make it even better (sort of!)