Candles, oil lamps, gas lamps are all alternatives, each with its own set of problems:
1 - candles -- smoke and do not put out enough light; produce heat
2 - oil lamps -- smoke, but produce more light than candles. Kerosene (the commonly-used oil) is still a fossil fuel (candles are made from fat)
3 - gas lamps -- produce the highest amount of light, but also give off considerable heat. Also, they use a fossil fuel.
Halogen and Sodium-based bulbs are also used, but each has its drawbacks.
Halogen lighting can produce intense light, much too bright for room lighting, but great for spotlights, headlamps, and outdoor lighting in general. Patio lighting is limited because of the intense light produced by such lamps.
Sodium lamps are limited more by the light spectrum they produce than by the amount of light.
Florescent lamps, when broken, release a toxic gas and often contain toxic material in their starters and ballasts).
LED lights produce intense lights that when improperly used, can cause blindness. But by far, they use the least amount of electricity and can be powered by hand-cranked power. They produce a very intense light, but because of their size, are limited in scope. I would love to see more lights that incorporate LED technology.
Of the alternative, LED technology currently has the advantage, but because it is relatively new (with respect to replacing incandescent lighting in the home), is still very expensive.