Solar Power

Also look at Nuclear Power


Efficiency of solar energy conversions.

http://www.stratosolar.com/uploads/5/6/7/1/5671050/high_temperature_solar_concentrators.pdf


On midday of Saturday May 26, 2012, solar energy provided over 40% of total electricity consumption in Germany, and 20% for the 24h-day. The federal government has set a target of 66 GW of installed solar PV capacity by 2030, to be reached with an annual increase of 2.5–3.5 GW. http://en.wikipedia.org/wiki/Solar_power_in_Germany

http://www.gizmag.com/solar-orc-reverse-air-conditioner/23696/?utm_source=Gizmag+Subscribers&utm_campaign=6c1b0d89fb-UA-2235360-4&utm_medium=email

An empty plastic bottle, litre of water, few spoons of bleach -- that's all that the students of IIT Powai needed to bring light to the homes of slum dwellers in Gowandi.

Inspired by Isang Litrong Liwanag's campaign carried out successfully by the My Shelter Foundation in the Philippines, students of the department of metallurgical engineering and material science decided to bring light to the dingy rooms of Mumbai slums. “We saw the simplicity of the solar bottle bulb and wondered why we couldn't implement it to lighten up slums in Mumbai,” explains the group that worked for over four months to bring the simple yet ingenious idea to life -- “litre of light”.

A Solar Bottle Bulb is a clear water bottle filled with tap water and a little bleach, this bottle is then embedded into the roofs of houses, with part of the bottle outside, and part of it inside. “The water inside the bottle makes the light omni directional, mimicking an electric light bulb. The bleach keeps the water clear for years,” Jaydeep Soni, third year student and member of the team, said.A Bottle full of Light

How to pipe daylight into buildings http://en.wikipedia.org/wiki/Light_tube

Don't know why the wiki above says sunlight direct went off market in 2009. They seem to be active
Sunlight Direct