**3. Renewable energy**

The focus today appears to have shifted from conserving fossil fuel to renewable energy. More literature today is dedicated to renewable energy, than to conserving the remaining fossil fuel reserves. This focus on renewables may create false expectations among consumers about the true capabilities of renewables. There is generally little awareness among consumers about the the limitations of alternative energy. The switch to alternative and renewable energy involves large capital investment, especially for solar and wind power. In spite of the research, renewable energy accounts for as little as 1.8% of global energy consumption today, up from 0.6% in 2000.

## **3.1 Solar energy**

In spite of efforts at solar power for at least two decades, implementation has been difficult because of low power intensities, large capital costs, and difficulities incorporating with existing technology. Silicon panels are much the same as the silicon chips used for microprocessors, and have similar requirements and constraints for manufacture. Silicon panels are expensive, and the area needed for a household (excluding air-conditioning) is barely met by panels all over its roof. Consumers are mostly unaware that solar panels can at best about convert about 25 % of the solar energy falling on it. Usage at night requires expensive and bulky batteries, which must be replaced every few years. Dependence on batteries can be reduced or avoided, by selling solar energy to the grid, as being by practiced by some household users in Europe. The utilities are cautious about accepting solar energy from others, as it introduces noise into the power grid.
