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.

Background: The transformation of the global energy sector from fossil-based fuels to low/non-carbon fuels will reduce environmental pollutant load, which in turn will benefit human health. However, with upscaling of emerging renewable technologies and energy sources, it is important to identify the potential for unintended health impacts, and to understand where the knowledge gaps lie with respect to health. We aimed to identify these gaps by conducting a scoping review. Methods: We conducted a systematic search of Medline, Web of Science, PubMed and EMBASE.

This study presents three cost-optimal calculations. The overall aim is to provide a deeper analysis and to provide additional guidance on how to properly implement the cost-optimality methodology in Member States. Without proper guidance and lessons from exemplary case studies using realistic input data (reflecting the likely future development), there is a risk that the cost-optimal methodology may be implemented at suboptimal levels.