ABSTRACT
The burning of fossil fuels is the prime culprit in global warming. Unfortunately, the fossil fuels have two substantial advantages over renewable energy sources — portability and energy density. It is easy to tote a 10-liter can of gasoline that contains about 120kWh of energy. A large, lead 60-amp-hour acid car battery with volume about ten liters has a maximum of 0.72kWh of energy. To make things even worse, to drain a lead acid battery is to seriously damage it; that is, it will no longer be able to store 60 amp-hours of energy.
