From 1,000GW to 63TW: NREL sets massive solar target for global decarbonisation

The National Renewable Energy Laboratory (NREL) says an “unprecedented ramp-up” of solar production capacity will play a crucial part in the global effort to avoid climate catastrophe.

A new study published in the journal Solar by researchers from NREL says that the world will need to see a 60-fold increase in the amount of installed PV from the current 1TW that is installed today.

The study’s authors also send the message that this task is eminently doable, although the NREL research appears to be focused on the decade between 2050 and 2060, a decade behind most science-based deadlines for avoiding runaway global warming.

“To avoid climate catastrophe, the world needs to decarbonise the energy system between 2050 and 2060, and photovoltaics (PVs) are expected to play a major role,” write the authors of the report.

Working under the assumption that “all presently significant electrical applications would be provided by PV,” the authors calculate that “the total installed PV generation capacity has been estimated to be 63.4 TW” of installed nameplate PV capacity.

By modelling such a PV production ramp-up the NREL researchers demonstrate that it is possible to meet these lofty goals as long as “investors continue to make financially rational decisions avoiding stranded production assets and therefore protecting their return on investment.”

To reach the decarbonisation target chosen by the NREL researchers solar manufacturers will need to scale up production capacity to reach 2.9-3.7TWh per year within 10 to 15 years.

Such a production ramp-up is expected to cost between $US600 billion and $US660 billion.

Importantly, though, the NREL researchers conclude that this ramp-up can be reached using existing technology and using expected further cost reductions in the maturation of solar technologies that use silicon and cadmium telluride.

The report also doesn’t ignore newer solar technologies such as perovskites and tandem photovoltaics that combine existing solar technologies and disruptive ones in a single much-higher-efficiency package but concludes that these technologies must first be proven to the market.

If proven, however, these “disruptive” technologies could be deployed at about a terawatt annually and could potentially be cheaper to manufacture than silicon PV on a per-watt basis.

Looking beyond the decarbonisation goal, Jao van de Lagemaat, director of the Chemistry and Nanoscience Center at the US Department of Energy’s NREL, said that a “relatively modest demand” in additional PV will be required even after global decarbonization is reached so as to keep up with module retirement and population growth.

This would result in an expected shock to the manufacturing industry where “suddenly much less manufacturing capacity is needed after decarbonization is achieved.”

Among the assumptions made by the researchers in their modelling was that, after the decarbonisation goal is reached, solar PV manufacturers will likely be reluctant to build new factories due to the drop in demand. New factories, which would generally boast a 15-year lifespan, would likely only be built in or around the decarbonisation date “if they are projected to sustain full output throughout their lifetime.”

The researchers also posit that deployed module lifetimes will continue to increase, with “module warranted lifetime [to] increase from a 2020 average of 30 to 50 years by 2040”.

The authors also acknowledge that the 63.4TW target of solar PV capacity “represents an upper bound” and might be undercut by the role of disruptive solar technologies, or non-solar renewable sources such as wind energy.

“There are economically viable trajectories that get to the needed manufacturing capacity to produce the amount of PV needed to completely decarbonize the world’s energy economy,” said van de Lagemaat.

“Emerging technologies could potentially lower the cost of this deployment significantly if they get commercialized in time.”