In an era of U.S. energy abundance, the persistently high energy bills paid by low-income households is troubling. After decades of weatherization and bill-payment programs, low-income households still spend a higher percent of their income on electricity and gas bills than any other income group. Their energy burden is not declining, and it remains persistently high in particular geographies such as the South, rural America, and minority communities.

Assessing the extent of evidence available relating to the impact of solar energy for households (HHs) in developing countries, surveys are reviewed focusing on the impact of pico‐photovoltaic (e.g., solar lanterns) or solar home systems (SHS) on rural HHs and directly related economic activities of their occupiers. Ninety‐eight documents have been analyzed. Areas of enquiry have included the impact of small individual solar photovoltaic systems on different facets of the life of HHs' occupiers: their education, health, finance, livelihoods, and social relations.

The review of policies being implemented in China, the EU, India and the US presented in this report has also identified some key challenges that we must address if we are going to realize the mitigation potential of the building sector. Chief among these is the need to improve our monitoring of the impact that our policies are having. Lack of measured and verifiable data on the influence of policies on building energy performance currently hampers our ability to assess and continuously improve their effectiveness.