Trigeneration is no ‘big mistake’

The Greater London Authority’s (GLA) processes ensure each scheme is considered on its merits, and many developers and consultants have responded positively to embrace the challenges associated with delivering low-carbon solutions in new developments.

The key London Plan energy policy (4A.7) contains a requirement to incorporate energy efficiency and renewable energy technologies wherever feasible, in support of the mayor’s energy strategy.

When the plan was published in 2004, following public consultation and public examination, it became clear energy was not always being considered as an integral or early part of a development’s design process. Planning conditions were allowing energy to be dealt with at the detailed design stages, but this was limiting the feasibility of combined heat and power (CHP) or trigeneration and renewable energy technologies.

The GLA therefore requires all new developments to demonstrate that sustainable energy measures have been fully considered as an integral part of the development process, and requests up-front feasibility work. Once we have established what is feasible we must apply policies 4A.8 on heating and cooling systems, and 4A.9 on renewable energy.

The GLA’s heating and cooling hierarchy sets the preference for solar water heating, then CHP for heating and cooling. Its processes require a demonstration of the feasibility of all energy measures, not just CHP/trigeneration.

In London there is therefore clear planning policy supporting trigeneration, which has nothing to do with political expediency, as suggested by Dr Thonger. GLA staff will continue to work with applicants to make sure all the mayor’s planning policies are implemented.

Allan Jones of the London Climate Change Agency has written separately to rebut the technical basis of Dr Thonger’s discussion of emission factors.

On 18 June the examination in public into the mayor’s further alterations to the London Plan opened. The main matter before this examination will be the mayor’s new climate change polices, which re-emphasise the gravity of the situation and restate the importance of CHP for London as part of a wider package of measures that will help meet the mayor’s ambitious carbon reduction targets for the city.

Contrary to Dr Thonger’s assertions and the BSj 05/07 cover headline, this is no “big mistake”. The use of trigeneration can result in significant carbon savings, and it will continue to be an important technology to help reduce London’s contribution to climate change.