The terms carbon-free and renewable are often used in similar contexts, but these two resources create different environmental and economic impacts. For example, MCE’s standard service, Light Green, is a minimum of 60% renewable and, in 2019, was also 90% carbon-free. So, what does it mean when energy is described as carbon-free or renewable, and why does it matter?
When energy sources are labeled carbon-free, the energy is produced by a resource that generates no carbon emissions, such as nuclear or large hydroelectric. Although these resources help reduce greenhouse gas emissions, they may impact the environment or the economy. For example, the waste produced by nuclear power plants needs to be safely stored long term, which can be cost-intensive. Additionally, the creation of dams to build new, large hydroelectric resources has lasting environmental impacts on the surrounding ecosystems.
Renewable energy, on the other hand, is classified as a naturally replenishing resource that produces zero emissions. Renewable energy sources include solar, wind, geothermal, biomass and biowaste, and eligible hydroelectric. The energy projects may create additional environmental benefits on top of their emissions reductions, such as pollinator-friendly solar programs, or economic job benefits, through the construction of new projects.