Solar Energy

Strong research in solar cells is producing many interesting projects to increase power output.

Advantages

Energy can be produced near where it will be consumed (solar panels can be put on the roofs of houses).
Good complement to wind power, as most windy days are not sunny just like most sunny days are not windy.

Drawbacks

Solar panels require silicon, currently in short supply. As silicon output increases (it takes 3 years to build a new plant to produce silicon), other bottlenecks may be the silicon ingot- and wafer-makers, or the ones producing the specialist chemicals that coat cells.
Solar energy has been subsidized by governments in Germany, Spain and the US. Now cuts in these subsidies bring uncertainty to demand.
Solar cells get dirty, reducing their power generation.

Solar research/innovations

Innovative financing schemes: Article about 2 utilities that pay all of the cost of installing solar panels on your rooftop. In addition you get a share of the revenues generated (electricity is sold to the grid by the utilities, with reduced line loss and less paper work for them than the construction of a new plant).
Hydrosol-2: New method for solar-heated two-step water-splitting thermochemical processes operating at temperatures below 1500 K, sponsored by DLR (the German Space Agency)
Nicole Kuepper: Inventor of cheap low-temperature solar cell manufacturing without costly equipment.
GreenField Solar: Builds high intensity solar cells and concentrators of solar light and heat.
New solar cell material: Comprised of a hybrid of plastics, molybdenum and titanium, it fluoresces and phosphoresces, using the visible spectrum of light energy.
3-Dimensional Nanotube Solar Cell for Visible and UV Light: William Yuan has designed a 3D solar cell that works for visible and UV light, which makes it highly more efficient and powerful.

Thin Film

Thin films of solar cells are roughly half as efficient (meaning that a panel must be twice as big to generate the same amount of power) as standard crystalline solar panels, but a third cheaper (watt for watt) and way more versatile - they can be mounted on a variety of materials including flexible plastics and fabrics.

First Solar: The biggest force in the thin film industry. It makes its cells from a chemical called cadmium telluride.
Nanosolar: They believe that a combination of copper, indium, gallium and selenium known as CIGS will prove cheaper to produce on a mass scale than cadmium telluride-based thin films.

Space Solar Power (SSP)

Around the clock, 1.3 gW of solar energy pour through every square kilometer of space around the Earth. Space Solar Power is an attempt to catch this energy and beam it to isolated places or vehicles.

Space Island Group: Plans to build large SSP systems piggy-backed onto empty fuel tanks converted into living quarters.
Solarbird: Mitsubishi Electric bets on squadrons of small satellites orbiting in formation.

Solar Associations

Swissolar: Swiss association of solar energy professionals.