Progress, opportunities and challenges of achieving net-zero emissions and 100% renewables

Abstract

• Renewable energy is now the major source of new electricity supply globally. • Greenhouse gas emissions must be cut rapidly to avoid worsening climate impacts. • Future solar PV market potential for addressing climate change is substantial. • Technically, a net-zero emissions or 100% renewable energy system is feasible. • Successful technologies, policies, and financing drive the energy transformation. This paper reviews the status and prospects of global renewable energy deployments and their contribution to the total energy supply. Substantial renewable energy capacity expansion has occurred over the past decade due to decreasing costs and favorable policies. Globally, the power sector saw 256 GW of renewable power capacity added in 2020. The contribution of renewable energy to the other major end use sectors - transport and heating - is more modest. Major policy drivers for renewable energy deployments are coming from climate mitigation initiatives, including the 2015 Paris Climate agreement to limit global warming to no more than 1.5°C. To achieve this goal, GHG emissions need to be cut in half within the next decade, and to reach “net-zero”, by 2050. However, recent analyses show that current pledges by national governments are far less ambitious than need to be taken to remain within the 1.5°C limit. Several studies demonstrate how the 1.5°C limit can be achieved through large scale, and perhaps even 100%, renewable energy deployments. These studies conclude that a transformation to a fully decarbonized energy system, making extensive use of renewable technologies, is not only technically feasible based on current and emerging technologies but also results in a lower-cost energy system overall, creating significant market opportunities for renewables. For example, the solar PV market growth under these scenarios would be 10–15% annually over the next three decades–well within the growth levels the industry has experienced thus far.