There is no law guaranteeing a right to energy from renewable sources, meaning that users could have their work undone by a developer plonking a building in their sunlight

Anyone spending thousands of pounds installing renewable technology expecting to save money in the long term should be concerned that they have no right to unimpeded access to the source of that energy.

In English law you may acquire a right to light by prescription (through long use or by it being granted to you) but this right is limited to the light passing through an aperture into a room.There is no right to sunlight or to a view, and as was demonstrated in Hunter and Others vs Canary Wharf Ltd [etc], you cannot even guarantee a right to a TV signal.
It is not mandatory for planning authorities to consider the amenity value of daylight and sunlight in and around a development and this only applies to habitable rooms and open spaces.

If we are to meet the ambitious target of cutting CO2 emissions by 80% by 2050, PV panels need to work hard

Increasingly, planning authorities and funders are requiring applicants to incorporate renewable technologies within their scheme proposals, usually expressed as a percentage of energy requirements for the development. Photovoltaic (PV) panels or tiles provide cheaper electricity for the occupants, and the possibility of a feed-in tariff for the owner.

When calculating the area of PV panel required, and therefore the amount of energy and CO2 emissions saved, factors such as orientation and external obstructions are taken into account. The output of these panels is sensitive to changes like overhanging trees or new buildings being constructed, both of which overshadow the panels, and power output falls significantly for relatively small changes.

So the PV panels are a planning requirement, but once installed there is nothing that would prevent a developer from constructing another building immediately in front which renders the panels almost useless. Added to this, if we are to meet the very ambitious target of cutting CO2 emissions by 80% by 2050, PV panels need to work as hard as possible

Even if it were possible to amend the rights of light law to allow PV panels to gain a right, they generally have a life expectancy of only 25-30 years and prescription requires 20 years’ use before a right is acquired.

The solution must be to afford protection through the planning system. This though does not protect those installations that have been made voluntarily by people wishing to lead more sustainable lifestyles. It might be possible to afford the same protection through planning or permitted development rights, if the proposed obstructing development requires planning approval, but what if the location chosen is unreasonable in that it would prevent any sensible development of adjoining land?

One mechanism that would, in theory, work for most scenarios would be to require the Environmental Impact Assessment to take account of PV panels surrounding development in much the same way as we undertake daylight and sunlight assessments. Another area we have reviewed at Calford Seaden is to have a mechanism of compensation attached to a calculation of loss similar to a right of light agreement. We are proposing a mechanism termed the “renewable energy reduction indices” (RERI). This would calculate the loss of renewable energy (CO2) generation caused by the overshadowing and make an award based on the projected life of the panels over a 25-30-year period. In this case the financial implications could be taken into consideration, but the loss of CO2 reduction would still be an area of concern.

It may be possible that the RERI award could be linked to provision of the lost energy from a green energy provider, or the provision of additional renewable energy technology given as part of the agreement where this is possible and practical to balance the CO2 requirements. What is important is that both the financial and emissions reductions are dealt with equally to preserve the very reason we have the renewable energy technology in the first place.

The growth in the renewable energy market over the last five years with the introduction of feed-in tariffs and renewable heat incentives (RHI), indicate a major development area for the future. With new developments having to become more aware of their immediate location impact a way of protecting renewable generation must be found, and quickly.

Peter Defoe and Terry Keech are partners at calfordseaden