Analysts have been underestimating the expansion of solar energy for nearly two decades, scientists report in a new study released last Friday. And that could be a serious problem for the industry and, maybe, the planet.

If policymakers believe solar is growing more slowly than it actually is, they may be less likely to prioritise the kinds of research and development that will help better integrate renewables onto the grid, such as improving battery storage technology. This could lead us to continue relying on more carbon-intensive energy sources.

“I think the most important risk is that the regulatory environment does not adapt in time to a rising share in solar energy,” said lead study author Felix Creutzig, a professor at the Mercator Research Institute on Global Commons and Climate Change, based in Germany.

The paper comes just a day after the release of a much-anticipated study on the electric grid.

The new paper, published Friday in the journal Nature Energy, points out that the deployment of solar energy has consistently outperformed the predictions made by so-called ‘integrated assessment models,’ which are commonly used to evaluate the ways different social, economic and technological factors might mitigate climate change, since at least the year 1998.

The researchers outline a number of reasons for the discrepancy.

For one thing, models have often failed to account for the policies different nations have put in place to speed the expansion of renewable energy

Additionally, the study notes, the costs of solar panels have been falling faster than expected. And the models may have also been overly optimistic in their assumptions about the expansion of other low-carbon technologies, such as nuclear power or carbon capture and storage technology.

David Victor, an energy policy expert at the University of California in San Diego who was not involved with the new research, suggested that solar’s relatively small share of the global electricity market also plays a significant role.

“When market share is small, big shifts in policy or technology can have a huge effect on growth,” he pointed out in an email to The Post. These types of sudden changes, and their aftermath, may be difficult for models to account for.

Victor also expressed caution about some of the researchers’ concerns.

For instance, he noted that the plummeting costs of solar equipment are all well and good - but other industry costs, such as the price of installing and maintaining solar systems, are not falling as rapidly. This is important to keep in mind when considering the industry’s overall performance.

In general, though, the paper ‘strikes me as basically right,’ Victor noted.

While it may seem like good news that solar is performing better than expected, underestimating its potential could pose some serious problems in the future. If policymakers are dismissive of solar’s future potential, they might fail to adequately prepare the grid for its continued expansion.

And there are, indeed, preparations that must be made for solar energy to successfully integrate onto the grid. Because solar is what’s known as an ‘intermittent’ energy source — meaning it can only generate electricity at certain times, while the sun is shining — significant improvements must still be made in the realm of energy storage technology to accommodate higher shares of solar in the existing power system.

Either that, or grids must adapt in other ways, such as by adding fast-ramping assets, like natural gas plants, that can kick in quickly whenever solar fades.

So accurate forecasts of the industry’s future could make a big difference in what’s prioritised now. And according to Creutzig, scientists are beginning to discuss ways to improve the models.

“It was a very long time that these models ignored the issue, but it has changed, and I think the next generation of models will look differently,” he told The Washington Post.

In the meantime, he and his colleagues created an updated version of a commonly used integrated assessment model as an example of how addressing some of the faulty assumptions can make a difference.

In either case, the future of solar energy may depend more heavily on our assumptions about its potential than has previously been suggested. And this means getting the models right should be a new priority.

— The Washington Post Service

Published in Dawn, The Business and Finance Weekly, August 28th, 2017