Solar Thermal Economic Madness
I have just had a quote for a 1403kWh/a solar hot water system land on my desk - the figures are very similar to the official website which is trying to sell us the systems.
The cost of installing a typical solar water heating system is around £4,800 (including VAT at 5%). Savings are moderate - the system could provide most of your hot water in the summer, but much less during colder weather.
For peace of mind some installation companies offer an annual service check.
You should have your system checked more thoroughly by an accredited installer every 3-7 years, or as specified by your installer. It is likely that after this period of time the anti-freeze that is used to protect your system in the winter months will need to topped up or be replaced as it breaks down over time reducing the performance of your system. Anti-freeze lasts better if the solar water system is used throughout the year and not left unused during the warmest weeks of the year. This cost of replacing the anti-freezer is usually around £100.
The other thing that your installer should check is the pump. In a well maintained system, pumps can last for ten years plus and usually cost around £90 to replace.
Based on the results of our recent field trial, typical savings from a well-installed and properly used system are £55 per year when replacing gas heating and £80 per year when replacing electric immersion heating; however, savings will vary from user to user.
Typical carbon savings are around 230kgCO2/year when replacing gas and 510kgCO2/year when replacing electric immersion heating.
Am I missing something here? £4800 to save a maximum of £80 a year, except the costs of servicing will be about £10 a year on the pump and £20 a year on antifreeze all plus labour. So the servicing will probably cost more than the savings. Life expectancy of system? 25 years?
There is a £300 grant on installation and the promise of a renewable heat incentive in the future but it all appears to be madness. All to save half a tonne of CO2 a year which I could buy for about £5.