Household energy interventions aimed at reduction of greenhouse gas emissions in low-income settings have greater potential to improve public health than do those in high-income countries, but household energy interventions in high-income settings are vital for the achievement of climate-abatement targets worldwide and also have appreciable potential benefits to health. In this first paper in the Lancet Series on Health and Climate Change, Dr Paul Wilkinson (London School of Hygiene and Tropical Medicine, UK) and colleagues analyse case studies of the UK and India to model the effects of various household energy interventions.
For the UK, the authors found that a strategy of combined insulation, ventilation, fuel switching, and behavioural changes would avert 5,500 premature deaths and save 41 megatonnes of carbon dioxide (CO2) in one year. Building fabric improvements would entail substantially better insulation of walls, windows, floors and roof, while improved ventilation would mean reduction of air leakage as well as installation of mechanical ventilation and heat recovery systems in suitable homes. Indoor household fuel pollutants would be removed by switching all household fossil fuels to electricity, and energy could be saved by reducing thermostat temperatures. The costs associated with such energy efficient refurbishment will be substantial but offset by significant savings in fuel costs.
However, the authors note that, for UK housing interventions, the magnitude and even direction of health effects depend on how energy efficiency measures are implemented and maintained. There is potential for adverse effects in some dwellings arising from such changes owing to i) increases in indoor pollutant concentrations, including radon and environmental tobacco smoke, if energy efficiency measures reduce ventilation, and (ii) increased penetration of outdoor particle pollutants with higher ventilation rates in dwellings fitted with mechanical ventilation systems unless there is control of external pollution levels or effective filtering of incoming air. Actions can be taken to reduce such potential adverse effects where they are recognized.
For India, the authors specified a 10-year programme to introduce 150 million efficient low-emissions household cooking stoves. This scenario was chosen because of the major public health burden that is associated with indoor air pollution from inefficient burning of biomass fuels in India and in many other low-income countries. The cost would be less than an initial US$50 per dwelling, with a similar cost for replacement every 5 years or so, partly offset by household fuel cost savings and time savings in collecting fuel. The cookstove programme in India showed substantial benefits for acute lower respiratory infection in children, chronic obstructive pulmonary disease, and ischaemic heart disease. The authors estimate that if the cookstove programme in India is fully implemented then, by 2020, 87% of Indian households would have very much cleaner combustion and air, and the total number of averted premature deaths from acute lower respiratory infections will have reached about 240 000 children aged younger than 5 years, and more than 1•8 million premature adult deaths from ischaemic heart disease and chronic obstructive pulmonary disease will have been averted. The estimated burden avoided in the year 2020 would be equivalent to nearly half the total burden of cancer in India that year in terms of lost healthy life years.
The authors conclude: "The evidence adds to the case for acceleration of mitigation because of the probable health benefits, and shows the effects of different forms of intervention in high-income and low-income settings. Housing interventions in the UK have a greater effect on reduction of CO2 per dwelling than they do in the Indian case study, and are essential for that reason alone. However, the health benefits, although generally positive, are small by comparison with those of improved cookstove technology in India, showing the large burden that is associated with inefficient burning of solid fuels... Improvements in the household fuel sector offer important potential benefits for health of women and young children as well as for mitigation of climate change."
Dr Paul Wilkinson, London School of Hygiene and Tropical Medicine, Keppel Street, London, UK. T) +44 (0)20 7927 2444 E) paul.wilkinson@lshtm.ac.uk
London School of Hygiene and Tropical Medicine Press Office. T) +44 (0) 20 7927 2073 / +44 (0) 7790 992797 E) Sally.Hall@lshtm.ac.uk / gemma.howe@lshtm.ac.uk
For full Series paper 1, see: http://press.thelancet.com/tlhacc1.pdf
Journal
The Lancet