Solar

=Solar=

Solar power comes from the sun: two types below. Supplies less than 0.02% of the world's energy needs in 2008.

__**Photovoltaics (direct)**__ Uses photoelectric effect: photons from sun liberate electrons, creates voltage which is electricity.

Advantages
 * Clean in operation (manufacturing?)
 * Major advances in Europe in PV power
 * Creates jobs
 * Possible to power almost 15% of world by PV by 2030 (EPIA/Greenpeace)
 * Solar energy is 6000x more than world's needs
 * Vast empty Sahara for PV park, lots of sun
 * Individual homes can use solar power through PV roofs
 * Proposed higher power (250 MW High Plains Ranch)
 * Efficient (already about 40%) compared to fossil fuels

Disadvantages
 * Expensive
 * Takes up space (can be solved by placing on rooftops)
 * Far less power than CSP type below
 * Less power generated compared to conventional fossil fuel sources
 * Max power currently from Olmedilla Photovoltaic Park (60 MW)
 * Compare to conventional sources:
 * Bruce Nuclear Generating Station by Lake Huron, 6/8 reactors on, currently 4640 MW
 * Three Gorges Dam (projected 22500 MW by 2011)
 * Typical fossil fuel plants are ~500 MW
 * Canada is far from equator, less solar radiation
 * 150 W/m^2
 * Compare to Sahara, >300 W/m^2
 * Uneconomical for homeowners, it would take around 20 yrs to offset the initial cost of installing PV roofs
 * Transmission losses (7.2% in U.S. 1995), 4-12% lost in conversion from solar power station produced DC to transmission line AC.

__**Concentrating solar power (indirect)**__ Functions by concentrating solar energy using mirrors and tracking system and heating up water to steam or concentrating onto PV cells (see above).

Advantages
 * Similar advantages to PV, cannot be placed on roofs however
 * Proposed 500MW+ farms (e.g. 600 MW Rancho Cielo)
 * Efficient (50% expected in future) compared to fossil fuels

Disadvantages
 * Similar disadvantages as PV
 * Cannot be placed on rooftops

__**Experimental: Solar Updrift Tower, Thermogenerator (more later)**__

==[Most of the info above is from just an overview, so that we get an idea of solar power. Taken from Wikipedia, articles on: solar power, photovoltaics, concentrating solar power. Also see the European Joint Research Council's Institute for Energy, fantastic scientific publications and info there for all kinds of energy sources]==