London's Poverty Profile: Map of the Month - energy efficiency ratings

At a time of soaring energy prices and the worst cost of living crisis in a generation, the cost that Londoners pay for one of the most basic needs - heat and power - has become a key issue. Much of the capital's housing stock is old and notoriously expensive to heat, even before the current energy crisis.

Our two new maps looking at energy efficiency in the capital show outer boroughs are going to be hit particularly hard by the crisis. With a clear ring of red around the capital, outer London, be it Havering, Bromley, Harrow or Kingston-upon-Thames, clearly has an energy efficiency problem. Energy costs in these areas may mean those wanting to move to the historically more affordable outer suburbs might have to rethink.

Domestic Energy Efficiency Ratings (2008-2021)

Carrying out an energy efficiency assessment has been a mandatory part of selling or letting out a dwelling in London for several years, and the register of energy performance certificates is public open data, published for the purposes of independent energy research. The Consumer Data Research Centre has aggregated, analysed and mapped three million energy performance certificates issued for London properties across the last 14 years - N.B. some properties may have received more than one rating, all ratings are included - calculating an average score and corresponding energy efficiency band for each of London's ~8000 "LSOA" statistical areas across the full time range.

By mapping at this level of detail, a clear pattern emerges, with new-build-heavy areas along the River Thames in central and east London showing clearly higher average energy performance scores (and so lower energy bills), along with other large-scale redevelopments such as in the London Olympic Park and Wembley Park. Tower Hamlets, in particular, stands out as a borough full of energy-efficient homes, no doubt due to its large housebuilding programme, and wholesale regenereation of many of its council-owned properties, across the last few years.

Domestic Energy Efficiency Ratings by Borough (2008-2021)

There will generally be a natural tendency for the centre of many cities, including London, to score better, as higher population densities mean they are more dominated by flats which benefit from natural insulation by their surrounding properties and more modern building design. This effect can certainly be seen in the City of London and the "Zone 1" areas surrounding it to the north, east and south - but intriguingly not the west, where Kensington & Chelsea has few energy-efficient areas - averaging across the borough, as in the second map here, shows it shares inefficient characteristics with outer London boroughs rather than its near neighbours (N.B. the two maps use slightly different colour scales).

But the overall trend is clear from these two maps: there is a ring of red in the capital. The housing stock in London's outer suburbs might be cheaper, and look attractive and historic, but are the running costs sustainable for modern living?

1 April 2022