Renewable and alternative energies

The world's population consumes about 15 terawatts of power, a business worth some $6 trillion a year (1/10 of the world's economic output). Renewable and alternative energies (hydro, wind, solar, geothermal, waves, biomass and waste, biofuels) represent already some 17% of this production.

This web site aims at providing information about the current state of renewable and alternative energies and future prospects.


Hydro

By far the largest source of renewable energy, hydro-electric power produces about 15% of the world's electricity, compared with 3% for other renewables, with still lots of room for growth. New Energy Finance, a research firm, reckons that less than one-third of the world's potential capacity has been developed.

Thousands of data centers, filled with thousands of powerful computers, consume lots and lots of energy, rivaling aluminum smelters in the energy they consume. Often just as much power is needed for cooling them as for computing. Building them close to a dam solves both issues in an optimal way.

Advantages

Drawbacks


Wind

World capacity of wind power is growing at 30% a year and will exceed 100 gigawatts in 2008 (about 1% of world-wide electricity use).

Modern wind turbines extract about 50% of the wind power, close to the theoretical (Betz) limit of 16/27 (59%).

Advantages

Drawbacks

Wind research/innovations

WhalePower
Increases blade efficiency with bumps on the leading edge (biomimicry inspired by humpback whales).
Ti'éole
Helps you to build a wind turbine yourself, for your own garden, with cheap material.
wind engine using boat sails<7a>
The sails moved around a fixed vertical axis. Free technology. In French.
boat sails prototype
Video in French of a prototype using boat sails that still works with very little wind.


Solar

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

Advantages

Drawbacks

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).
Kender solar
An attempt to harness the solar heat stored in the air as much as direct solar light. Sponsors this site.
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.


Experimental

Experimentations at the edge of science. Might work. Might not.
BlackLight Power
An attempt to release latent energy from the hydrogen atom.
Cavitation heaters
Mechanical energy applied to weirdly shaped rotors with holes that would create over-unity heating (more energy produced than was put in the system).



References: