Anyone who has sat through the It’s A Small World ride at a Disney park knows the inspirational (if repetitive) message the animatronic dolls are singing about. We may all come from different cultures but deep down, we’re all the same. It’s a small world after all.
But outside of the Disney parks, the world is actually vast. Although we can fly to other countries easily enough or video conference over great distance, we are still essentially separated by geography— especially when it comes to electricity. One big idea that could help connect us: a common electrical grid or as it’s sometimes called, a supergrid.
A recent report from the United Nations outlined how creating an interconnected power grid, that would move electricity from one region or even country to another, could help foster peace and cooperation between nations.
That might sound like a pipedream but it’s not. The technology needed to build a global supergrid exists today in the form of High Voltage Direct Current transmission, also known as HVDC. GE is one of the few companies in the world that can provide this system.
Currently, the majority of power grids use AC (alternating current) which moves electricity in a wave-like motion. This is useful because most of today’s consumption devices use AC, but you can’t efficiently move this form of electricity over extremely long distances. The wave-like flow causes the conductor that carries the electricity to charge and discharge very rapidly which results in an annual loss of about 10 percent of all electricity generated. HVDC solves this problem by moving the electricity in a direct current (DC) at a constant voltage which is easier on the conductor and requires less space. With HVDC, we can transport up to 3 times more electricity on conventional HV lines while reducing energy losses. The keys to making the HVDC transmission system work are the converter stations at the beginning and end of each line. At the beginning, the convertor changes the incoming AC to DC and at the other end it switches it back. That way the electricity is in the form of an alternating current when it gets to your home but it travels there as a fast moving, more efficient direct current.
GE is already supplying these converters on several HVDC lines around the world — a number of which are being used in concert with renewable power. In the United States, GE will potentially be working on an HVDC project that could take power from a wind plant in Oklahoma and deliver it to stations in Arkansas and Tennessee. And, the massive DolWin3 off-shore wind farm in Germany will use GE’s HVDC system to get power back to shore. Other land based projects just recently demonstrated the maturity of the technology to move massive amounts of power or exceedingly long distances. Rio Madeira in Brazil will operate at 600kV and will transmit power nearly 2,400 kilometers … the longest operational HVDC scheme in the world. And with the Champa project in India, we are demonstrating the transmission of power over 1,365 kilometers at an even higher voltage of 800kV.
In addition, baby supergrids are already in the works all around the world. In Europe, energy providers in Germany, Denmark and the Netherlands are looking into building a supergrid that would harvest wind from the North and Baltic Seas and open up a broader market for wind power. In Asia, officials in China, South Korea and Japan are considering a supergrid that would help increase renewable energy in the area, reduce electricity costs and promote cooperation between the nations.
Potential Global Supergrid
With these and other projects, the groundwork is being laid to build a global supergrid. And it would be much more than just a feel-good exercise. Joining the power grids of the world together could create the right market for renewable energies to truly take off. Right now, most renewable sources can only serve populations within a certain radius of generation and within those regions, output from those sources can be unpredictable. The sun doesn’t always shine. The wind doesn’t always blow.
A recent report from the IEEE points out that a region of Australia, south of Darwin, gets enough consistent sun that a solar farm “the size of a cattle station” could provide enough energy for the entire country. HVDC has the potential to move that energy around Australia. With an underwater link, that energy could also move to places like Indonesia, Papua New Guinea and Singapore.
In addition, think of how efficient it would be to have energy from renewable sources going to where it is most needed at any given time and alternative forms of energy (hydro power, fossil fuels) available as back up.
A global supergrid could open up the electricity market to the lowest-cost form of energy at any given moment. It could also guard against blackouts. In developing countries, consistent energy can be a luxury. With a supergrid, growing nations could improve the quality of their power supply without having to build new power plants, instead leveraging the low cost of generation available through the connected network. A supergrid could also be safer and more stable. Small, localized power grids are often at risk of going offline due to storms or malfunctions. A supergrid actually helps the performance of local AC networks as well as provides additional capacity that otherwise wouldn’t be available.
We won’t get a worldwide supergrid tomorrow. Nations would need to work together toward a logical plan of connected projects as opposed to the smaller scale projects that are being built today. But the prospect is there. We have the technology. All we need now is the will to get us to a truly small and connected world