Electricity as an energy currency

Electricity is the classic example of an energy currency. The biggest reason that electricity is such a popular energy currency is its flexibility; electricity has many more uses than a primary energy source like oil (oil is a fuel, but it must be turned into something useful to a consumer). Electricity can run household electronics and electric lights, cook a meal, heat houses, or even run an electric vehicle. Electricity is the most flexible form of energy now and for the foreseeable future. This is why electricity use is growing faster than energy use, see figures 1 and 2.

Electricity provides much of the power that is needed for maintaining a high energy society. Even though electricity provides energy, it is not a fuel. Even though electricity flows through wires, it is not a flow. Electricity isn't a primary energy source because electricity is always produced from some fuel or flow. Electricity is rather a way of moving and using the energy from those primary sources.

Electrons do not inherently have useful energy. Rather, power plants and batteries put energy into electrons, which can be harvested at the other end by electronics for energy services.

The single biggest drawback of using electricity as an energy currency is that it is very difficult to store electricity. Electricity generated on the electrical grid must be used immediately (within thousandths of a second after it's produced). This is why energy storage technologies like pumped hydroelectrical storage and batteries are so important for intermittent power sources like wind power and solar power. The electrical grid must carefully monitor demand in order to make sure that enough electricity is produced to meet the immediate demand.

To get some idea of how electricity is growing compared to total energy look at the line chart below. This shows that the flexibility of electricity creates a strong incentive to have as great a fraction of energy produced in that form as is possible. To get some specific details, click on different years and notice how the fraction of the total final consumption that is electricity grows with time (for most countries). Click on different countries on the map to find country specific data.