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Power Points

24/7 carbon-free energy could be cheaper than you think

Turns out, decarbonizing power is cost competitive for Peninsula Clean Energy in California.

3 pictures, one showing wind turbines across a hilly landscape, one showing solar panels, and one showing batteries to store renewable energy

Image via Peninsula Clean Energy Report, Achieving 24/7 Renewable Energy by 2025

I often write about 24/7 carbon free energy (CFE) — the concept of matching energy use with clean energy supply in real time. I find it endlessly fascinating: it is technically feasible, incredibly difficult and critical to decarbonization. That mix of urgency and complexity has stoked friendly competition between corporate climate leaders such as Google and Microsoft, making the conditions right for breakthroughs.

One of the largest barriers to decarbonizing power is cost. Our cheapest sources of energy — solar and wind — are weather dependent, meaning they must be partnered with more expensive, firm technologies, such as energy storage or geothermal, to meet our energy needs all day, every day. 

But Peninsula Clean Energy (PCE), a local utility in northern California, is challenging that assumption. Using a new modeling tool called MATCH (a backronym for Matching Around-The-Clock Hourly Energy), PCE says it has a path to cost competitive, carbon-free energy by 2025.   

The utility found it is able to reach clean energy 99 percent of the time at a price point that is only 2 percent more than just procuring enough renewable energy to offset their annual electricity consumption — a far less ambitious and far more common goal from companies and municipalities. 

How will a local utility reach 24/7 CFE — without breaking the bank?

Reaching 24/7 CFE on a large scale will require a variety of tools, including load shaping and shifting to demand better match when energy is generated. Peninsula Clean Energy, which is trying to reach this goal in two short years, isn’t relying on customers to adopt new technologies or change behaviors. 

Instead, its model relies on overbuilding renewable capacity, which it says will leave very few hours where there is not enough supply to meet demand. To meet needs 99 percent of the time, the utility predicts it will need about 50 percent excess capacity, according to calculations spelled out in a white paper. It also assumes it can resell excess energy for resource adequacy or as renewable energy credits. 

Getting that last 1 percent, however, appears to be much more costly, requiring PCE to build 80 percent excess capacity. My 2 cents: 99 percent is pretty dang good, and, if every organization followed suit, would position us well to achieve climate goals.  

Of course, these findings are highly specific to Peninsula Clean Energy. The utility enjoys the temperate weather of the Bay Area, meaning there isn’t much demand for air conditioning in the summer or heaters in the winter. The modeling also focuses on just one year — 2025 — and costs will ultimately be dictated by market conditions. The calculations also assume the technologies will be available and deployments will happen on time. 

But the findings challenge the notion that reaching 24/7 CFE will always be prohibitively expensive. And the new open source tool invites companies with deep decarbonization goals to game it out. So — what’s stopping you?

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