PROJECT EASY GREEN

If General Fusion can fulfill its goal of generating power from nuclear fusion, it could mean scientific immortality for the small Canadian company.

The company is working on a reactor that will, ideally, fuse two different isotopes (deuterium and tritium) of hydrogen into a helium molecule that will also release neutrons tremendous amounts of heat. The heat in turn can be exploited to produce steam for an electrical turbine.

A power plant based on the technology might cost $1.50 to $2 per watt to build, according to Michael Brown, a partner at Chrysalix Ventures, the lead investor in General. That translates to around 5 cents a kilowatt-hour for fusion power, or less than coal, natural gas or any other form of electricity in the world.

“This is basically a heat engine,” Brown said. “Deuterium is cheap. Lithium is cheap. The fuel costs of any reactor would be 1/1000^th of a penny per kilowatt.”

But don’t get the wrong idea: Brown isn't a misty-eyed dreamer. Like nearly everyone else who has studied fusion, he understands the monumental task ahead. General will inject a hydrogen plasma heated to one million degrees into a steel sphere three meters across with half-meter-thick walls filled with a spinning mass of liquid lithium and lead.

Two hundred pistons surrounding the chamber then begin to beat a precise rhythm: accuracy needs to be within 10 millionths of a second. The pistons create a shock wave that forces the metal to the center, causes the spinning vortex to collapse and in general lets the magic of thermonuclear reactions take place.

Simple.

“The whole thing was dreamed up in 1975," he said, but the controls to coordinate such a feat couldn’t even be found on Star Trek back then.

However, if a technical shortcut the company has been developing works out as planned, General thinks it can demonstrate the technical feasibility of the concept sometime toward the end of 2012. A prototype reactor could potentially be ready by 2018 with commercial reactors coming on-line in 2023. Amazon's Jeff Bezos is an investor too.

Lawrence Livermore Lab and Tri-Alpha have fusion projects underway, as well. The formidable challenges involved in the undertaking have naturally made many skeptical. Both Ernie Moniz, director of the Energy Project at MIT, and Admiral Frank Bowman, who now runs the Nuclear Energy Institute, remain wary of fusion.

Does scientific glory await in the relatively near future? Or will scientists still be toiling in the lab?

What do you think?

Read more on this topic in a joint effort by General Electric Ecomagination and Greentech Media, and join in on the conversation here.

Solar power and wind power are usually the first topics that come to mind when the discussion turns to renewable energy sources.

The global solar footprint has grown almost a hundredfold, from 175 megawatts in 2000 to 15 gigawatts in 2010. But despite the growth of those sectors, wind and solar still account only for a tiny fraction of global electrical generation, which is dominated by coal, natural gas and nuclear power.

Conventional hydroelectric power currently provides about seven percent of the electricity in the United States. But the lack of new sites and tight environmental regulations ensure that there won't be a lot of growth in large hydro — never mind the efforts to dismantle existing dams to restore fisheries.

But dams are not the only way to harness hydro power.

Startups are innovating and looking to use wave power, tidal power and power from river currents to drive turbines and create electricity. Water is 800 times more dense than air and tides can be predicted decades in advance. But what if you took Neptune's fury out of the equation? The microhydro firm Hydrovolts has a turbine for irrigation ditches that could turn farms into power plants. Beyond that, there are osmotic pressure gradients and ocean thermal technologies that, at first glance, seem to border on magic.

There is also enormous power below our feet: geothermal energy from naturally occurring underground steam sources. While most geothermal wells are now in the western U.S., hot dry rock (HDR) geothermal power could expand the footprint because it doesn't rely on natural underground reserves. A recent MIT study estimated the available portion of HDR power to “exceed 200,000 exajoules, or 2,000 times the annual consumption of primary energy in the United States in 2005."

Unfortunately, it's not fully tested, and HDR has the potential to create some seismic activity.

New technologies in energy storage are also emerging — fuel cells, flow batteries, phase-change materials, flywheels, pumped hydro, and compressed air energy storage (CAES) — as are new types of nuclear reactors. Most of these technologies are in the experimental stage. Which ones will make it to maturity?

Read more on this topic in a joint effort by General Electric Ecomagination and Greentech Media, and join the conversation here.