The world is bathed in enough sunlight to meet humanity's energy needs many times over, but the best places to harvest that light and the places where it is needed seldom coincide. The old dream of transmitting power from the deserts to cities thousands of kilometers away may be on the verge of coming true with two giant projects under development. The more advanced of these intends to run undersea cables from Australia to Singapore and has just received support from the Indonesian Government, through whose waters the cable would run.
As the second most densely populated independent nation on Earth, Singapore is particularly ill-suited to generating its own energy. Currently, its electricity relies largely on fossil-gas-fired power stations. With so much of the island's residences and offices being sky-scrapers, rooftop solar could only power a small fraction of the buildings below. This has inspired the idea of building vast solar farms elsewhere and transmitting the electricity to Singapore.
Sun Cable, a company established by some of Australia's wealthiest individuals has the most ambitious plan. Originally proposed as a 10 GigaWatt plant near Elliot, one of the sunniest places on Earth, the vision has now grown to a 17-20 GW behemoth. For comparison, by 2008 there had been only 14 GW of photovoltaic cells installed in the history of humanity.
If the project goes ahead powerlines will carry the electricity produced 800 kilometers (500 miles) to Darwin, where a small portion will be used to power the city. The rest will be sent through a High Voltage DC cable that will wind between Indonesian islands to Singapore. During the sunniest part of the day, some of the electricity will be used to charge a 36-42 GWh battery (30 times larger than the current world record) to keep the recipient cities powered well into the evening.
The goal of the project is not just to provide Singapore with clean energy and make a profit for the investors. The project is also intended to kickstart a much larger Australian solar industry. Despite having invented the most widely used solar cells in the world, and having abundant sunlight, Australia produces almost none of the solar cells it uses today. Sun Cable hopes the secure demand they will be offering will change that.
Mike Cannon-Brookes, one of Sun Cable's primary investors, is also putting money into SunDrive – who are seeking to commercialize technology that replaces the silver in solar cells with cheaper copper – and 5b, who have invented cheaper ways to install solar farms.
If Sun Cable succeeds it will also light a path for similar projects elsewhere. This week a 10.5 GW solar/wind farm in Morocco was announced, with the intention to send power 3,800 kilometers (2,400 miles) to the UK. The project is a year or two behind Sun Cable's in development.
Others, however, have more local plans for powering Singapore. Recognizing the shortage of land, Singapore has built floating solar plants on local reservoirs, but these are too small to provide even 1 percent of the city's needs. Duriankang Reservoir in Indonesia's Batam Island is much larger, leading to a proposal to build a 2.2 GW floating solar farm there, with the electricity sent a modest 50 kilometers (30 miles) to Singapore.