The 20% house – An integrated assessment of options for reducing net carbon emissions from existing UK houses

This paper takes an integrated analysis approach to explore the options available for a UK homeowner to reduce their domestic emissions to the level advised by the UK governments Committee on Climate Change of 20% of those associated with a typical house in 1990. It uses proven thermal models of a typical house and low carbon heating systems to estimate the emissions associated with domestic heating and electricity consumption from a number of combinations of low carbon micro generation technologies. The amount of additional low carbon electricity needed to offset these emissions to the desired level was then calculated. The capacity of photo voltaic panels needed to generate it was then estimated. This has been done over a range of different grid carbon intensities and the resulting configurations have been subjected to energy analysis and financial appraisal. An environmental life cycle assessment was also undertaken to see if there were any unacceptable environmental consequences of an owner adopting any of the options. The research shows that in all cases operational GHG target can be met, but that emissions associated with the production of the systems is variable, meaning that with current technology a 25% house is more likely. It has also been shown that given current subsidies the installation of some of the proposed systems should be financially attractive to the home owner.