The Optimal Path to 100% Decarbonization for California: Webinar and Whitepaper

Can a state meet its renewable power targets ahead of schedule and save billions of dollars in the process? According to results from a new Wärtsilä whitepaper, “Path to 100% Renewables for California,” this way may be the optimal path forward for California.

The state is currently paving the way toward a clean-energy, decarbonized future — setting an ambitious goal of 100% renewable electricity by 2045, which relies heavily on solar, wind and battery storage. Ensuring affordable and reliable power; however, presents major hurdles in meeting this target.

In a recent webinar, “California’s Faster, Cheaper Path to 100% Clean Power,” Wärtsilä energy experts presented an “Optimal Path” forward for the state, based on their study. Using Plexos Energy Simulation Software, the experts — Jussi Heikkinen, Antti Alahäivälä and Joe Ferrari — found that powering California by only solar, wind and battery storage will be extremely costly in the long run and not result in full carbon-neutrality by 2045.

The Optimal Path, unlike the current plan, leverages power-to-gas (PtG) as a long-term storage alternative, where carbon is recycled from air, so combustion of PtG methane is carbon-neutral with no increase in atmospheric CO2 levels. In a 100 percent carbon-neutral power system with a ban on fossil fuels, PtG and its use in existing or new thermal power plants is considered a form of long-term storage.

With the Optimal Path, renewable energy will serve the majority of the load, traditional battery storage will handle day-to-day balancing, and PtG with the thermal fleet allows for longer-term balancing and reliability. See the figure below for an installed capacity breakdown through 2045.

The Optimal Path allows the state to meet full net-zero carbon compliance by 2045 (as recommended by the IPCC), while also minimizing air emissions, land use and energy costs relative to that envisioned with current plans, saving ratepayers billions of dollars in the process. Overall, the Optimal Path to 100 percent decarbonization for California’s electricity sector:

  • Reaches the state’s current renewable target five years ahead of schedule and full net-zero compliance by 2045
  • Lowers carbon emissions between now and 2045
  • Leads to $8 billion in savings
  • Dramatically reduces land use, grid connections and curtailment of solar and wind power
  • Provides security of supply with long-term energy storage using renewable fuel

The plan also avoids flexible thermal capacity becoming “climate stranded” in 2045, avoids overbuilding, improves grid reliability and leverages existing gas storage capability and distribution systems.

The experts identified three steps California can take to realize the benefits of the Optimal Path.

  1. Keep legacy thermal plant retirement dates in place—no extensions
  2. Allow for replacement capacity of optimal proportions solar, wind, Li-Ion storage and strategic amounts of fast-start, flexible thermal
  3. Formally recognize thermal plants running on renewable fuels as net-zero carbon assets guided by legislation or regulation.

Highlighting the value of their results in the webinar, Heikkinen remarked, “the Optimal Path proves decarbonizing the power system doesn’t have to cost a fortune.”

Miss the webinar? Watch the recording here or view the presentation. Want to learn more about their modelling and results? Download the whitepaper here.