Guardian: Government incentives are about to make solar water heating panels a financial no-brainer for millions of households across Britain, as long as they have a south-facing roof. Two weeks ago Guardian Money outlined the attractiveness of electricity generating panels as a result of the introduction of “feed-in” tariffs, which will pay households for the extra energy they produce. However, the installation cost – at around £12,500 – will put many people off. Less off-putting are …