Connecting global power sources could beat climate change
By Stewart Taggart, 2 March 2009
It's the grid's equivalent of Internet broadband. Known as Ultra-High Voltage Direct Current (UHVDC), it could end the 'tyranny of distance' in electricity transmission. The positive global implications are hard to overstate. Development and deployment of UHVDC could mean geothermal, wind, concentrating solar power and other clean energy sources are no longer hobbled by distance from existing transmission infrastructure.
In the short term, UHVDC could mean lower greenhouse gas emissions. In the medium term, UHVDC could mean increased cross-border trading in electricity, lowering prices and increasing grid reliability. Over the long term, UHVDC could increase global political stability by deepening multilateral energy interdependency.
UHVDC combines two existing 'off-the-shelf' efficiencies and combines them. The first is direct current (DC) power. DC transmits electricity over long distances more efficiently than alternating current (the kind used by consumer devices). The second is high voltage. By pumping up voltage, more electricity can be transmitted across a given line. The current leading edge of UHVDC development represents just an incremental step forward, raising new cable capacity (to be deployed in China ) to 8,000MW and 800kv from previous maximums of 6,000MW and 500kv. Already, some envisage 10,000MW UHVDC cables being developed to service proposed North Sea wind farms.
Rising global per capita energy usage, the integration of China and India to the global economy, aging current global electricity transmission infrastructure and the need to combat climate change all point to increasing UHVDC deployment in coming years. The good news is that this is happening at a time when the world electricity system needs a major upgrade. Nearly US$30 trillion must be spent on energy infrastructure globally before 2030 to avoid chronic blackouts, according to the International Energy Agency. The lion's share of that money will go to generation and transmission infrastructure, the IEA estimates.
China is staking a claim to leadership in UHVDC power. The Chinese government is laying huge (6,000MW), long distance (2,000 kilometer) UHVDC power lines from country's western hinterlands, where hydro and solar resources exist, to its eastern cities. Bigger UHVDC cables (8,000MW) are expected soon. Having China develop this technology could ultimately represent a gift of China to the world as significant as China 's previous contributions: paper, gunpowder and the compass.
China has plans to lay dozens of UHVDC power lines from west to east. This will catalyze the UHVDC industry and the rest of the world should watch with approval and encourage China . If China develops a competitive UHVDC industry, China 's economy will be able to satisfy more of its internal electricity needs from cleaner sources of electricity than coal. But best of all, China 's development of a UHVDC industry could hasten the day when a 'Pan-Asian Energy Superhighway' could be built connecting China and Australia . Such an energy highway would encourage development of large scale renewable resources in the Asian region, increasing cross-border trade in 'green' energy and deepening multilateral energy dependency, thereby enhancing geopolitical stability.
Encouraging China to develop a global-competitive UHVDC industry will be immensely positive for the world. No other country can afford it at this time. Meanwhile, China 's own huge infrastructure needs make such investment largely unavoidable. If China builds up a UHVDC industry while the west concentrates on economic reform and reconstruction following the credit crisis, everyone comes out ahead. That's because large-scale cross-border investments in UHVDC power lines could be considered sometime after 2015. This in turn would spark a virtuous global cycle of increased development of renewable energy, lower electricity costs and reduced greenhouse gas emissions.
Keep an eye on Chinese UHVDC. It could end up as the 21st Century's "killer application" when it comes to combating climate change.