エネルギー：カリフォルニアにおける太陽エネルギーの公平な導入を配電網の制約が制限している可能性

Electricity grid limits could not only constrain the future uptake of distributed energy resources in California, USA, but also exacerbate existing racial inequities linked to the adoption of solar energy, according to a study published in Nature Energy.

Potential increases in current flow — brought about by household solar photovoltaic systems — can lead to high temperatures and voltages that can constrain the electricity grid to which these systems are connected. As such, in any given electric circuit, the number of households that can install solar electricity generation is limited. Solar energy adoption at the household level is known to exacerbate existing racial and economic inequities, namely as a result of the upfront investment needed. However, the relationship between grid hosting capacity and these inequities has not yet been examined.

In order to analyse potential limits to the integration of new distributed energy resources, Anna Brockway and colleagues mapped the grid capacity of California’s two largest utility territories. These results were then analysed in conjunction with corresponding demographic data. The authors reveal that, under current conditions, the grid only has enough capacity to support less than half of the households in these territories with the adoption of solar photovoltaic systems to meet all their electricity needs. Grid limits were also found to reinforce demographic disparities in access, with Black-identifying and disadvantaged communities having disproportionately less grid capacity to host renewable solar energy at the household level.

The authors conclude that these grid capacity limits suggest the need for significant infrastructure upgrades, and that racial inequities should also be a priority when designing the policies for such upgrades.