(Image:reve.art) 
A recent exchange of heated emails has again seen me at the centre of a raging debate about the efficacy of solar energy (at least with respect to grid-scale generation). One would have thought that this issue had long been put to bed, but it hasn’t. Numerous furious objections still pop up like whack-a-moles, not helped by the US administration’s contempt for the whole enterprise.
Unfortunately, the debate about the technology of solar is very difficult to separate from the roiling seas of climate change politics. But they are very different matters.
On 28 April, the Spanish energy grid collapsed, taking Portugal out with it. Within hours of the event, as the authorities were struggling to bring systems up again, theories started circulating about the cause — from terrorists to human error to sunspots. Now it is widely accepted that Spain’s grid solar ecosystem, one of the largest in the world at 25% of installed capacity, was most probably responsible.
How so? Ignoring the gnarly details, suffice it to say that traditional energy generation and distribution ecosystems are designed to ramp up and ramp down gracefully in response to demand, even in the case of sudden unexpected events, and this mechanically dictated torpor (the large turbines) serves to keep the grid stable.
Solar generation systems, not so much — they have no turbines taking time to speed up and slow down. This means that a big solar system is much more liable to fall over completely and instantaneously when some anomaly appears. It is called the inertia problem (I am ignoring the important details of a matter called frequency synchronisation — critical, but deep in the technical weeds).
When you are a country that has as huge an interconnected renewable ecosystem as Spain, this causes a cascading effect — one solar plant knocking over the next one, like dominoes. And that, according to most grid engineers I have read, was the cause.
It was not as though the solar engineers who built these systems did not understand the inertia problem; it is rather that robust solutions to the problem are advancing more slowly than the raw energy-producing capabilities of photovoltaic cells. There was insufficient protection against these events.
It is an engineering problem, but not an unsolvable one. The inertia problem is neither a systemic flaw nor a permanent Achilles heel. It will be solved, but hadn’t been solved as of 28 April. One may take the position that solar systems were rushed into production before all the kinks were ironed out (which, in the light of events, is almost certainly true), but that is an indictment of political wrangling unrelated to the actual technology and what solar promises.
Intermittency problem
A second objection to the deployment of grid-scale solar is the intermittency problem. Where does the power come from when there is no sun? There are two places — batteries or traditional power station redundancy, like coal or nuclear. Batteries are not enough, and they are relatively expensive. No grid-scale plant can afford more than 12–24 hours of battery back-up (the last time I checked) to be commercially viable, even with subsidies.
Again, this is not a foundational problem. The trendlines of battery efficiency per kWh are astonishing — with plumes of innovation spouting everywhere and an endless flow of urgent venture capital pouring into the sector. AI-assisted electrochemical research is also forging ahead. One of these, funded by Microsoft, has already led to an electrochemical solution that uses 70% less lithium than previously.
Yes, it is true that batteries are not yet up to the task of carrying a solar plant through long sunless periods, but it is not a valid objection against the deployment of solar power. Follow the improvement trend, not the transitory snapshot.
The final oft-repeated objection relates to the need for state subsidies to support solar (and other renewables), without which they couldn’t survive. This argument leaves me cold. Not only does the fossil fuel industry receive massive subsidies, from tax breaks to government land for power stations, but, more importantly, many new industries, from locomotives to the internet, received state support until they were able to swim on their own. State subsidies are important and virtuous for any promising young industry.
This points to a deep logical flaw in the anti-solar narrative. Its core argument is that it cannot compete with fossil energy in reliability and cost today. One can argue against that, of course (there are currently profitable grid solar plants running without subsidies), but it misses the most important point: when the prize is as significant as cheaper/faster/better/cleaner energy, today and tomorrow are two very different lenses on possibility. One could even argue that abundant and free energy is the foundational aspiration for our civilisation; there is nothing more important.
It is true that many solar and other renewable projects have been put into service prematurely under the considerable pressures of climate politics and sometimes shrill alarmism. But here is a simple thought experiment that blunts the argument against large-scale solar power. If there were no global warming, no climate movement, no activists and no Intergovernmental Panel on Climate Change would the development of solar power still be a good idea?
The answer is obvious. Cheaper, more efficient, clean. A couple of core and ultimately solvable engineering problems before we get there. Soon. Simply a better product than the one that has been used since the first fire was started.
It is difficult to see the downside. DM
Steven Boykey Sidley is a professor of practice at JBS, University of Johannesburg, a partner at Bridge Capital and a columnist-at-large at Daily Maverick. His new book, “It’s Mine: How the Crypto Industry is Redefining Ownership”, is published by Maverick451 in SA and Legend Times Group in the UK/EU, available now.