Is Oversizing Renewable Energy the Key to Net Zero?

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Often policymakers and planners assume that renewables plus storage are too expensive to bring online in large quantities, but a new report from the independent think tank RethinkX challenges that view.

renewables plus storage

By phloxii/

Rethinking Climate Change finds that it’s important to add these technologies, both in front and behind the meter, and to oversize the renewables portion, installing three to five times more generating capacity than is now on the grid — then add storage. This will allow nations globally to achieve net zero in the 2030s in a cost-effective manner, said the report.

In fact, RethinkX predicts that incumbent carbon-intensive industries in energy and transportation worldwide will collapse and be replaced by disruptive technologies such as solar, wind and storage by 2035 in a textbook case study of disruption.

“The exciting disruption ahead of us in the energy sector is being driven by solar PV, wind power and batteries,” said Adam Dorr, research fellow at RethinkX. “It’s the convergence of those three improving in cost that’s driving the disruption.”

The RethinkX report argues that solar, wind and storage will be cost-effective if the renewables capacity is oversized, requiring less storage — which is more expensive. With the higher levels of renewables and the right amount of energy storage, moving to 100% solar, wind and battery is not only affordable, but will be the least expensive electric system that can be built by 2030, Dorr said.

Microgrids as disruptors

“Microgrids will have a key role to play in this disruption,” said Dorr. Their specific roles will depend on local or state factors. “We, as a society, have to find what works best under different circumstances.”

The researchers developed what they call the “Clean Energy U-Curve,” which illustrates what’s needed to balance renewable generating capacity with energy storage capacity to ensure that renewables plus storage can serve electricity users 24-7. This applies to centralized and distributed generation, including microgrids.

At some point, energy from distributed energy resources (DER) — including microgrids — will become cheaper than energy from the conventional grid, said Dorr. “We are likely to see a wide variety of DER and microgrid energy models tested worldwide in a wide variety of geographic, social, and geopolitical conditions during the 2020s, which is exactly what we need to do in order to discover winning strategies,” he said.

The think tank took a unique approach to determining the cost of the energy resources.


Clean Energy U Curve image courtesy RethinkX

RethinkX’s October 2020 report and February 2021 report examined the capital costs of solar PV, wind and batteries, and concluded that the traditional levelized cost of electricity (LCOE) model (expressed in kWh) is flawed. What’s more, the per-kWh figures from sources like the US Energy Information Administration are inaccurate, the reports said. A more reliable source, the organization concluded, is power purchase agreements (PPA).

Worldwide, PPAs and similar contracts for solar alone are now priced below 2 cents/kWh, said Dorr. For solar plus storage, the cost per kWh varies depending on how much battery capacity is included. In the U.S., four hours of battery capacity, paired with solar, is as low as 3.5 cents/kWh, he said.

“These costs are significantly lower than the actual per-kWh LCOE of conventional coal, gas, nuclear and hydropower plants. In some cases, these costs are even lower than just the operating costs of conventional power plants,” said Dorr.

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With the costs of deploying renewable energy and storage dropping so quickly, these technologies will be accessible to people of all income levels.

“At a high level, these specific disruptions in energy and transportation and food, all of these are inherently democratizing technology. They have the potential to be an extraordinarily powerful force of democratization of access. For the first time in history, anyone is going to be able to access energy  clean energy — because you won’t need to build a $1 billion power plant with coal or nuclear power.”

In order to ensure the technological disruptions occur as quickly as possible, policy needs to change, said Dorr. That includes ending subsidies to the fossil fuel industry.

The report calls on policymakers to focus on moving the highest impact technologies forward, rather than implementing “whack-a-mole” approaches such as clean coal, behavior change and carbon taxes.

Disruption pressures policymakers

Throughout history, as disruptions have gathered steam, support from the public has grown, along with pressure on policymakers. As a result, the old technologies have eroded, he said.

“As these technologies ramp up, there will be an exponential growth curve and as they become more popular and affordable, society becomes more accepting of these technologies,” he said.

That leads to increased pressure on policymakers to support the disruptions.

One example is the demise of Kodak. It was the titan, but when the first digital camera became available, consumers began to adopt those cameras, and now Kodak is a memory, he said.

In spite of the organic disruption process, it’s important for consumers and members of the clean energy industry to push for policy that will accelerate the move to a zero carbon future as quickly as possible.

“We can speed it up or slow it down with our choices, especially with the clock ticking on climate change,” said Dorr.

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  1. “The RethinkX report argues that solar, wind and storage will be cost-effective if the renewables capacity is oversized, requiring less storage — which is more expensive. With the higher levels of renewables and the right amount of energy storage, moving to 100% solar, wind and battery is not only affordable, but will be the least expensive electric system that can be built by 2030, Dorr said.”

    I find this interesting as it points towards the boast of the economies of scale of the utility solar PV farms with energy storage. I have toured some housing tracts like Mandalay homes ‘Jasper’ tract that will have solar PV on every home’s roof and smart ESS Sonnen Ecolinx in every garage creating an aggregate 30 MWh of energy storage when the complex is built out. In the retail arena it seems like 4 to 6kWp of solar PV is needed for these homes and a 20kWh energy storage system that can be programmed as a VPP, resilience, or used as arbitrage in off peak hour energy storage as a grid service.

    I feel there is a paradigm in the utility sector that doesn’t allow the concept of solar PV farms and or wind farms to store any over generation day or night and can be used as time shifted dispatchable grid response any time of the day or night. One could have one large solar farm with several hundred MWp solar generation stored in a 1GWh ESS and it could be saved all day long to dispatch at night only, another plant could have (less) energy storage available but extend its generation day beyond and into the 4PM to 9PM portion of the day, this is why I believe the Engineering of utility energy storage should go beyond the 4 hour mark and into the 6 to 8 hour generation capacity. IF engineered as a “matrix” storage/generation system one could take a 300MWp solar farm array and store this energy all day long in a 1.5GWh battery field, matrixed into the ability to generate 100MWh for 15 hours or 250MWh for 6 hours or 300MWh for 5 hours. IF there are more than one transmission feeder terminating at this energy storage system, one could charge some battery assets from one transmission feeder and send them down the line later, on another feeder, creating energy shuttling for the day ahead market.

  2. The real conclusion of the rethinkx report is not about wind and PV energy more cheaper than coal, gas or hydro. Was my first thinking.

    The report just suppose a coal, gas and hydro capacity factor near zero in the future. Of course, with that assumption the LCOE will go to the sky in this technologies.

    And most important, the only scenario with low capacity factor in this three technologies will be if PV and wind capacity in the electrical system is 5 times bigger than the total actual installed capacity. Because coal, gas and hydro just will be used to support PV and wind ramp (up and down). In that case, PV and wind must to pay for this new ancillary services: up and down wind and solar ramp. In other words, pay for low capacity factor of coal, gas an hydro generation assets.

  3. Right out of the gate the poor in Germany were dumped off the power grid. That’s their “exciting disruption.” And after driving over the poor, the champions of wind and solar keep their mouths shut and their foot on the pedal. Will this stop with the poor, or is it a trend that will climb the food chain into the middle class? The advent of scarce luxury power, non-24/7 power? Listen to the degrowthers, then take away their pollyannaish rhetoric and replace it with the Ultra-Rich’s bribe powered extortion economy.
    –When will wind and solar champions, champion getting affordable power back to the poor?