Following the piece I did for BBC Country File on Feed in Tariffs, I found myself in an interesting debate in the letters section of New Civil Engineer. As usual, this started me thinking, this time about communicating sustainability to the public.

The standing of climate science is currently pretty low as it has become apparent that scientists overstated some of the issues. The same happens when Government makes overblown statements about the effectiveness of renewable energy in desperate attempts to meet its own policy targets.

The announcement launching Feed in Tariffs suggested that householders could earn £900 per year from installing PV. They failed to mention that this was only true for the South East of England, on a perfectly pitched roof, facing due South; hardly representative of the average. Further, such an array would be a little too large to fit on the roof of an average 3 bed terraced house and would cost £13,000-£15,000.

I believe that there must be much more clarity on the actual performance of real systems. We have already seen the market for DIY wind turbines killed off by public reaction to the overstatement of returns by manufacturers. This has reduced the choices for homeowners, even where these could have been installed in worthwhile locations. For engineers and Government to similarly hype up the potential returns from renewable energy does not do the industry any favours.

We need to build public trust and support for renewable energy by making realistic assessments of the returns they can expect from real installations, not theoretical ones.