From 2002 to 2007, more than 400,000 photovoltaic (PV) solar home systems (SHS) were sold in northwestern China under the US$316 million World Bank/Global Environment Facility-supported Renewable Energy Development Project (REDP). REDP has been hailed as a best practice example in SHS deployment for its unprecedented scale and the combination of technology improvement and market development support components to strengthen the country’s renewable energy industry. While the World Bank has itself conducted post-project evaluations, our paper presents the first independent review with the intent of determining if anticipated project impacts have been sustained. We adopt a case study format supported by in-depth interviews with the project’s relevant stakeholder groups and find that solar home systems (SHS) provide monetary and non-monetary benefits to users and that their portability complements the lifestyle of the region’s nomadic herders. However, we also find that purchasing decisions are still based on price more than quality, after-sales service networks remain weak, and households in REDP’s coverage area are gradually gaining access to hydropower-based grid electricity.