Pathways Toward 100% Carbon Reduction for Electric Utility Power Systems

Many states, cities, towns and utilities are committing to a 100% clean energy future. This push toward 100% is ubiquitous in the news, academia and politics. However, there is no clear or commonly accepted understanding of what this means. For example, what is the difference between 100% carbon-free and 100% carbon-neutral?

A recent Wärtsilä whitepaper, “Pathways Toward 100% Carbon Reduction for Electric Utility Power Systems,” breaks down these terms and examines the costs and carbon reduction trajectories associated with these 100% targets. It explores what these different definitions imply for utility systems as they transition from fossil-dominated to clean energy dominated.

The findings of the whitepaper point toward utilities leveraging power-to-gas (PtG) technologies to meet net-zero carbon emission goals, rather than 100 percent carbon-free. In examining the cost of a carbon-free system versus a carbon-neutral system, the analysis concludes that electric utilities can achieve 80 percent carbon reduction based purely on economics, with no subsidies, mandates or renewable requirements by leveraging PtG.

Carbon free may be the ideal solution for utilities that have ready access to hydro or other carbon free resources that can provide firm capacity when wind and solar falter. But most utilities do not fall in this camp and must explore a wider array of technical solutions to meet decarbonization goals. PtG provides an additional degree-of-freedom in the planning process that unlocks new and exciting pathways towards decarbonization. This work shows PtG pathways provide the lowest cost for ratepayers while simultaneously attending to climate change concerns.

The United States can lead in the path to a 100 percent renewable future by investing in PtG to provide a cornerstone of the path towards what the Intergovernmental Panel on Climate Change (IPCC) is calling for: carbon-neutrality. In general, PtG will be a large part of decarbonization for flights, sea-freight and domestic shipping and automotive, supplementing the strides we are making with electric vehicles. The investment in power-to-fuels is already starting and will accelerate.

This will provide positive feedback loops and interplay among the liquid fuels industry, the natural gas fuel industry, and the electric utility industry that will be beneficial for all three in meeting decarbonization targets. What may still be needed, is the legislative and regulatory vision to make this possible, or at the least, not stifle it.

For example, many states openly allow biofuels to count as “renewable” for power generation. Allowing the same for renewably generated power-to-gas would provide a great deal of incentive in the adoption of this technology and hopefully accelerate a 100% renewable future.