The solar debate heats up this week as one reader explains the reasoning behind the feed-in tariff cuts, while another draws our attention to a solar energy technology being left in the shadows

The missing energy link

As the country strives to meet its 2020 targets under the EU Renewable Energy Directive, one renewable heat source is being left out in the cold over what appears to be a question of semantics.

Solar air heating was designed to heat large spaces such as offices, warehouses and factories traditionally heated by gas systems. The technology uses a Transpired Solar Collector (TSC) or SolarWall to harness the sun’s energy, which is then used to pre-heat fresh air. This warm air is then drawn into the building’s heating system via a series of fans, making it an active technology. It is recognised as such in more than 34 countries including America and Canada, where the installation of the technology is incentivised to encourage take up.

However, under the Renewable Energy Directive (RED) TSC technology has been classed as passive, preventing its inclusion in the Renewable Heat Incentive Scheme and therefore rendering it less attractive as a renewable option for investors.

Solar air heating has the effect of dramatically reducing a building’s heating requirement, providing savings in energy consumption and carbon emissions.

Furthermore, the technology is easy to install, has the lowest capital cost, the highest known efficiency (up to 80%) and quickest return on investment of any active solar technology, with payback in as little as three years. It has already been installed for some of the UK’s leading brands.

A change in classification from passive to active, which after all will simply bring the RED definition in line with the rest of the world, would contribute to the UK meeting its CO2 emissions reductions targets but would also be a huge win for British manufacturing and the jobs that will be created by the uptake of this most efficient, active renewable technology.

Brian Watson, CA Group

FITs cuts were necessary

Regarding John Alker’s article “FITs due a haircut but government has butchered PVs” (2 November,, the government thinking behind this is that
feed-in tariffs in the future will be linked to the Green Deal. The properties that will be eligible will be those that already have the basics installed ie loft and wall insulation. The environmental impact of this is far greater and the payback far shorter. This open chequebook policy could only last for a limited period but the new system is fairer for those that have made an effort to improve their energy ratings.

Nigel Ives, via

River park sinks

Regarding your story “London may lose £60m river park”, (2 November,, the design of this “park” is terrible and London can do so much better - just look at the amazing High Line park in New York and everything that has been achieved for the local area.

It’s time for London to think bigger and bolder and other sponsors will then come along - we are supposed to be a world class city after all.

J Gimblett, via