Cypress Semiconductor may have sold its interest in SunPower, but it’s not getting out of greentech.

The chip company is incubating internal groups to study different green technologies, said CEO T.J. Rodgers in a meeting with reporters today. The company, for instance, has retained two PhDs to examine thermoelectric materials, materials that can convert heat into electric power. Wrap a layer of thermoelectric material around a steam pipe or an exhaust pipe and it could generate electric power for a factory or a car, he said.

Approximately half of the energy in the U.S. — 50 to 60 quadrillion BTUs out of 100 quads generated — gets wasted and a substantial portion of that energy is converted to waste heat. In the past few years, startups like GMZ Energy have formed to tackle this market. (more on that market here.)

Cypress has also created a group called Cypress Enviro Systems that is concocting components that can be used to control power consumption in buildings. Rodgers, in fact, showed off a component that can automatically control old time thermostats. Right now, old thermostats are pneumatically controlled. When you turn them down, what you are really doing is releasing air captured in a chamber — that’s that small whooshing sound you hear. Cypress came up a radio controlled thumb. A radio (hooked up to centralized bank of computers) sends a signal to the thumb — a component inside the thermostat. The thumb then moves the thermostat.

“It is the same old thermostat. It installs in five minutes. It is not going to be SunPower. It is not going to make billions of dollars� but it’s a start, he said.

The small gust of wind could also be used to generate the tiny amounts of power needed to control the radio-controlled automatic thumb. Cypress will also look at ways to harness vibrations. Some companies, such as Verve and EnOcean, have already come up with light switches that can harvest the vibrations created when someone flips a switch. The power from these vibrations is enough to power the switch via radio: thus, these light switches do not need wires.

Green has been good to Cypress. The company turned a $750,000 investment in SunPower into $2.5 billion. Technically, Rodgers actually did the investment in SunPower in late 2000 himself. Cypress’s board first turned it down. But later he sold it to the company for a fairly low price. At the time, SunPower, now a multibillion dollar company, was worried that it would have to lay off 20 of its 40 workers.

Rodgers, who likes to speak his mind, also said that the “time has passed� for companies to make it in CIGS, or copper indium gallium selenium, solar cells. Silicon solar cell makers will dominate the bulk of the market because they have large factories and a lot of experience in manufacturing. Cadmium telluride solar cells will do well in northern climates like Germany.

A noted libertarian, Rodgers also said the government should not give subsidies directly to companies. Subsidies can help jumpstart a market -- as in solar -- but by 2012, solar should be cheaper than conventional power, he said. Oil companies, he added, are already getting federal subsidies. So solar subsidies should remain to achieve parity.

The Mississippi River will be the site of a first-of-its-kind project aimed at harnessing the river's flow to create energy without dams or diversions. Houston-based Hydro Green Energy LLC said Monday that it has received approval from the Federal Energy Regulatory Commission to install two 100-kilowatt hydrokinetic power units in the river. The idea is to harness the river's flow to spin a turbine without the need to dam the river One unit will be installed this month and the second in April, and both will provide power to the town of Hastings, Minn., about 20 miles downstream from Minneapolis, the company said. Hydroelectric dams provided about 7 percent of the United State's electricity in 2006, by far the largest share of any renewable energy source, according to the U.S. Department of Energy's Energy Information Administration. But dams also block the migration of salmon and other fish species and wreak havoc on river ecosystems, causing many environmentalists to question their green credentials. Hydro Green is hoping its hydrokinetic power station won't cause such problems. The company said it will study its technology's impacts, which modeling indicates will have "no water quality and possibly no fish mortality impacts." Hydro Green landed $2.6 million in a Series A round in April, led by The Quercus Trust (see The Secret Life of the Quercus Trust). The company is now raising a Series B round to fund company growth and "an agressive defense of the company's intellectual property," the company announced Monday. CEO Wayne Krouse told Earth2Tech in August that Hydro Green was looking for $70 million for its second round. Hydro Green said it's working on other hydrokinetic power projects in Alaska, Louisiana, Maine, Mississippi, New York and Texas. Harnessing the power of ocean tides is also on the company's agenda, which puts it in the company of such startups as SMD Hydrovision, Marine Current Turbines, Open Hydro and Ocean Renewable Power (see Tide Turning for Ocean Power?)