Planting trees is a cost-effective way to reduce residential electricity consumption and abate atmospheric CO2

Reducing energy consumption from buildings' operations is a sine-qua-non for achieving a future with net-zero emissions. Could urban trees play a role? Several observational and simulation studies demonstrate the effect of vegetation on reduced energy consumption and this study confirms it, this time looking at densely populated areas in diverse climate zones. A comprehensive multi-year monthly electricity consumption data set representative of all of China, together with high-resolution NDVI (Normalized Difference Vegetation Index) data, reveal the relationship between an urban area's greenness and its residents' domestic electricity consumption. Findings show that for every 0.1 increase in the cities' NDVI, urban per-capita residential electricity consumption decreases by 1.76% (95% CI: 1.11–2.42%). This cut in electricity consumption results in life-cycle power-sector CO2 annual emissions reductions of 23.05–45.52 Mt., equivalent to 2.85–5.63% of China's total residential sector CO2 emissions in 2020, depending on assumptions on urban population's size and electricity sector's carbon intensity. Moreover, these cities' trees can store 247–284 Mt. CO2 over 30 years, so the present value of the net benefits, equal to monetized electricity savings plus carbon emissions' reductions and carbon storage minus tree planting and maintenance costs, is positive for 29 Chinese provinces (except Chongqing and Xizang) ranging between US$-0.84 and US$21,000 per tree (−6–156,485 yuan/tree). If not planted exclusively in urban areas but all over China, a carbon price of 267–1339 yuan/ton is needed to ensure the benefits cover the costs of planting and maintaining the trees.