The electric grid is quite recent, in the context of human history. Only 130 years ago, except for a few extremely rich early adopters in New York, our ancestors used kerosene lanterns and candles to provide light in the evening. Lighting was just about the only use for electricity for the first two decades of the 20th century. From these modest beginnings, we now have a world that is almost entirely electrified and this magic juice has changed our lives like few other inventions. Without electricity, we would not have telephone service, air conditioning, radios, televisions, computers, the internet or even high-rise buildings.

In the beginning electricity was provided almost exclusively by the private sector, although poles and wires were draped over pubic rights-of-way. Thomas Edison, George Westinghouse and others competed for market share, resulting in a patchwork of separate but overlapping electric networks that were consolidated and integrated in the first part of the 20th century by industrialists like Samuel Insull. The combined electric utilities were considered natural monopolies, since it made no sense to have separate sets of wires and transformers serving a single geographic area. As monopolies, they were regulated at multiple levels of government.

The federal government stepped into the electricity business during the great depression both as a regulator and supplier. The Tennessee Valley Authority and the Bonneville Power Administration were created as government corporations. Our largest federally-funded hydroelectric projects were constructed during this period.

Today, the electric grid is still primarily owned and managed by the private sector, but heavily regulated at all levels of government. Electric power producers are allowed to compete with each other at the wholesale level in most areas of the country, since the transmission and distribution systems are available for a fee to any power producer that wants to sell electricity into the grid.

The technologies used to make electricity vary widely in different parts of the country. The rust belt is almost entirely powered by coal and natural gas, while wind generators have a huge market share in Texas and Iowa. California has a little of everything including solar, wind, geothermal, hydro and natural gas. The carbon emissions per unit of electricity produced also widely vary from state to state.

Power from wind and moving water has been a source of energy for millennia, but this kinetic energy was not used to make electricity until Michael Faraday showed us how to convert rotation into electricity in the early 1800s. Hydropower is as old as the grid itself but growth is limited and some even think it is maxed out. In the last few decades wind and solar technologies have matured and are gaining market share.  Wind now produces more electricity in the United States than hydro and the generation share for solar has been rapidly increasing for the last decade, as costs continue to decline. Geothermal energy is limited mostly to the western United States where thermal wells can be drilled. And, there are serious questions about the sustainability of biomass.

If a utility or independent power producer wants to build a new plant and sell power into the grid, wind and solar are now as cost effective as natural gas and once the wind and solar plants are built, they cost practically nothing to operate. However, wind and solar are intermittent generators. Currently, gas is used to provide backup and to pick up the load at dusk, but batteries are beginning to supplement traditional energy storage techniques like pumped storage to fill the gaps and make wind and solar a more independent source of power.

This part of the book describes the electric grid we now have, how it is managed, and how it came to be. It reviews the utility-scale renewable energy technologies now used, evaluates their relative cost, and assesses their future potential.