Let solar shine
To realise the potential of solar power the world must take urgent, co-ordinated action to achieve universal energy access with renewables (“The Sun machines”, June 22nd). If we don’t 660m people, most of them in developing and emerging economies, will be still living without electricity at the end of this decade.
The most energy-poor countries are not able to access the green investment they need. According to the World Economic Forum, 81% of green investment in high-income countries is funded privately, compared with just 14% in emerging and developing economies. One area where this shows up is in the deployment of battery energy storage systems ( BESS). Without sufficient storage capacity, countries will be unable to add renewable energy to their grids at the scale they need to provide constant electricity, cut emissions and create economic opportunities.
Partnerships like the BESS Consortium aim to change that by making initial investments that ultimately usher in the private investors needed to make renewable energy the cheapest source of power. Solar power can transform the world, but only if we ensure poor countries are not left behind.
ASHVIN DAYAL
Senior vice-president
Rockefeller Foundation
New York
The depressing thing about your article on private firms driving a revolution in solar power in Africa is that it could have been written ten years ago (“The light continent”, June 22nd). The number of people without electricity in sub-Saharan Africa has not moved since 2014, when offgrid solar was still often cheaper than grid extension and South Africans were already battling power outages.
Then, as now, we are not doing enough to fund electricity infrastructure in countries that need it. The West heavily subsidised electricity grids when they were first built out; rural customers are still subsidised today. Yet we expect off-grid electricity to be profitable in Africa.
The World Bank and other donors pledged around $2bn to off-grid solar from 2012 to mid-2020, often with great fanfare. Just 13% of that money was disbursed over that time, even though private companies were poised and ready to build. We will be in the same place in 2034 if donors continue making grand promises that don’t materialise. We can’t rely on the private sector in Africa to shoulder the cost of connecting rural customers when they are the least profitable. Our aid institutions must put their money where their mouths are if we are to build solar infrastructure in Africa.
LUCY SHAW
London
I disagree with the claim that, once installed, the costs of solar systems become negligible. Solar parts, such as microinverters or microprocessors for optimising performance across modules or for monitoring the system, fail and must be replaced. Because the technology is advancing so quickly, the replacement parts usually reflect an upgrade in technical performance but at added expense. The parts are components in a system that are often “ganged” with other similar parts, so a failure of one part requires the replacement of additional parts in the gang that have not yet failed to assure compatibility.
Rooftop solar systems are often not synchronised with the roof’s life, so when roofing needs replacing the system must be disassembled, removed and reinstalled. If the building codes have changed the replacement system must be a new one, not the old one, so in effect the lifetime of a solar system is often cut short by the lifetime of the roofing on which it is mounted.
ALTON PENZ
Frisco, Colorado
As you say, Bell Labs unveiled a new technology for turning sunlight into power in 1954 (“The solar age”, June 22nd). Decades before that, in 1906, George Cove patented a solar panel and rudimentary battery. His company, Sun Electric Generator Corporation, demonstrated the technology on New York’s rooftops. He was allegedly kidnapped in 1909 (some claim by energy competitors) and abandoned this work shortly after.
I wonder what impact this might have had on our climate? If we shift solar power’s exponential growth back 40 years before 1954 (assuming no disruption in 1909) solar could have become cheaper than coal by as early as 1997. It’s a good reminder that vested interests can set back progress, a challenge that is as relevant today as it was back in the 1900s.
SUGANDHA SRIVASTAV
Smith School of Enterprise and the Environment
University of Oxford
Solar power has been a boon to the Amish, who don’t use electricity from a public grid. An Amishman in the community where I lived has a business installing solar panels and selling battery power tools.
JIM SEVERANCE
Spring Green, Wisconsin