What will it take for the U.S. to get a stable and affordable energy supply? A lot, says Byron King. The country is still dependent on carbon: coal, oil and natural gas provide 87% percent of its energy.

It’s not just a question of renewable energy and nuclear – you need to factor energy efficiency in there too, as well as improving the grid.

And as the transformation occurs there will be plenty of opportunities to profit. SunPower (SPWR), the largest U.S. solar-panel maker, recently reported 2Q net profit of $28.6 million, or 34 cents per share, compared with a loss of $5.3 million, or 7 cents per share, in the year-ago period. Definitely one to watch…

Coal. It’s dirty, and burning it generates massive amounts of CO2, which causes global warming. It’s also the America’s main source for power generation.

So what can be done, asks Greg Gunner Guenthner. Are there ways to make it cleaner? Carbon capture technology is a possibility, but it’s years away from being usable.

Oil is another massive polluter, and gets more expensive by the day. Looks like the only option is to invest in sustainable energy – the sooner the better.

Andrew Gordon has published a comprehensive downturn investment strategy guide. He picks seven sectors that he believes offer outstanding growth opportunities. Perhaps unsurprisingly, there is a clear commodity-based theme…

Costs for solar thermal energy will be cheaper than coal as soon as 2020, according to a report from the US Department of Energy, making one solar ETF a great way to profit.

Google, Chevron and Goldman are all betting that this prediction is correct. This from Bloomberg:

Unlike photovoltaic solar panels that convert sunlight to electricity, solar thermal focuses sunrays with mirrors to heat oil in glass pipes to about 700 degrees Fahrenheit (370 degrees Celsius).