Renewable energy is the excellent idea that energy should come from sources that can be counted on to continue to exist even after a great deal of use. Solar is renewable, because the sun will almost assuredly be shining next year, but coal is not because there is a limited supply, after which it will take millions of years to make more. Let me list some kinds of renewable energy.
Various types of panels absorb the radiant energy of the sun, and product electricity from them. Panels must be replaced every 20 or so years, as their production declines over time
Pluses: Most common during peak usage hours, awesome looking, little environmental impact, silicon is super abundant.
Minuses: Available an average of 12 hours per day, no production at night, fragile materials
Windmill turns when the wind blows, producing power.
pluses: Cheap, awesome looking, lasts a long time
minuses: Unpredictable, damage to birds
Grow plants, harvest them, dry them out, then burn them.
Pluses: Easy, uses existing coal infrastructure
Minuses: Smoke, excessive use of farmland
Like solar, except collected in space and then beamed down
Pluses: Higher availability version of solar
Minuses: Insanely expensive, severe problem if the beam ever misses
Get many people to ride stationary bikes really really hard.
Pluses: Excellent for fitness, Increased employment
Minuses: Not cost effective, financially, thermodynamically, or in any other way
A block of nuclear waste is encased in a jacket that makes power from the thermal difference between the waste and the surrounding environment
Pluses: Recycles nuclear waste, produces heat for cold climates, guaranteed for hundreds of thousands of years, portable, works underground, constant
Minuses: You have a block of nuclear waste in your house, and should the jacket be damaged in any way you are probably now a superfund site. Also, incredibly heavy (125 pounds produces 300 watts.)
Agricultural unwanted byproducts, like dead diseased turkeys, are thrown into a big pit and the methane from their decay is captured, and burned when power is needed
Pluses: Recycles what would otherwise be garbage
Minuses: Only practical near the farm, smells bad
If only this could be turned into a power source.
Pluses: Practically infinite supply
Minuses: No way of actually producing power.
Capture seawater as it flows up during high tide, then during low tide, it must flow through a water wheel to return to the ocean, producing power
Pluses: Will exist as long as the moon does, free after initial construction
Minuses: Only available on seashore, only produces power during low tide, need to remove sea life from captured pool
* Gravity Plate
Plate on sidewalk or street compresses when stepped on or driven over, producing power as it decompresses back into place.
Pluses: Interesting, unexpected
Minuses: Probably annoying, difficult to maintain
* Arc Plasma Gasification
Complicated system in which garbage is run through a plasma torch, converting it into a flamable gas.
Pluses: Garbage is now fuel, supply of garbage is extremely large and currently worthless. Will probably be garbage for as long as there is civilization.
Minuses: Complicated, hard to maintain, expensive to set up
Dam up a river, whose water must now flow through a water wheel to get downstream, producing power
Pluses: Easy, cheap
Minuses: Area behind damn floods, damage to stream's wildlife.
Earth's immense internal heat is used to boil water, which makes power.
Pluses: Free after initial setup, Abundant, perfectly clean
Minuses: Super expensive outside of plate boundary zones and near volcanoes.