The Grid: The Fraying Wires Between Americans and Our Energy Future

There is so much information to unpack in this book. In ‘The Grid’, Gretchen Bakke discusses the many limitations of the intricate and highly complex system of wires which supply electricity to millions of Americans. The grid is old; it is made of technology which hasn’t been upgraded in decades, and continues to suffer due to neglect. “More than 70 percent of the grid’s transmission lines and transformers are twenty-five years old; add nine years to that and you have the average age of an American power plant.” Overgrown foliage ignored by utilities often breach electrical lines and are the leading cause of blackouts in America. It is no surprise then, that blackouts now occur with increased frequency, and in an electricity-driven economy each blackout results in a loss in economic activity. “Six billion dollars lost: that’s $60,000 per hour per blacked-out business of lost revenues across 93,000 square miles.”

More recent developments in energy have exposed some of the more tricky problems with our grid. The grid was originally designed to deal with a steady predictable source of power generated at a centralized location, but the recent shift in energy generation away from fossil fuel power plants to distributed and variable renewable technologies, such as solar and wind, renders the grid obsolete in its ability to reliably supply power. Renewable power is growing at a meteoric rate in America (“In 2014, 53.3 percent of new generation installed in the United States was either wind or solar”), and many states like Hawaii, Texas and Vermont aim to predominantly generate their power exclusively from renewable sources within the next 30 years. However, the inefficiencies of the present grid have held back renewable power significantly. “Investments in renewable sources of power generation are failing or falling very short because America’s electric grid just isn’t robust enough or managed well enough to deal with the electricity these machines make.” Incorporating distributed variable generation via wind or solar is only possible via a complete reimagination of the grid.

One of the efforts to deal with this problem is to develop a “smart grid,” which will allow for real-time communication and optimization of electricity generation, consumption and storage between the various producers and consumers of electricity in the future grid. “Flows of power would be multidirectional as rooftop solar met backyard wind met big nuclear or hydro, and the output of all these types of generators would intermingle “intelligently” on the wires.” Another technology which promises significant improvements in grid resiliency are micro and nano grids. Micro/nano grids supply electricity generated on-site to a small area. Microgrids are not new technology - many university campuses, industrial complexes, military bases and more recently, silicon valley tech companies, generate and supply their own power and heating, allowing them to operate partially or completely “off-grid”. As distributed sources of generation, like wind and solar, or even other soft power generation technologies such as small hydro, biomass and geothermal, become more commercial and accessible, electricity consumers become electricity producers, which allows them to leave the grid and operate as pockets of microgrids. Since microgrids simultaneously incorporate several different generation sources, and are not dependent on a central power station or long high voltage transmission lines, the microgrid is much more robust.

One of the greatest drawbacks of the grid, and that of renewable technologies as well, is a lack of viable energy storage. Solar for example, produces most of its power during the day, but in the evening, when generation goes down, demand goes up, as people come home, causing utilities to ramp-up their fossil fuel power plants to meet the excess demand. Variable demand is expensive and inefficient. Ramping up power plants, or even solar and wind, is expensive and takes time, which makes the grid susceptible to outages during peak demand. “The sun is going down and with it a precipitous fall in generation just as demand is rising with equal ferocity. This evening peak is much harder for a utility to deal with when the sun is powering more than about 25 percent of the grid.” This is why storage is important - storing some of the solar power during the day to use at night will alleviate the stresses engendered on the grid by variable demand. There are many technologies which are being developed for storage. Many concentrated solar power plants use sensible storage in molten salts, some store the heat as latent heat in phase-change materials, and some use metal oxides with multivalent cations to store heat as chemical energy in reversible redox reactions. Other avenues of storage include pumped hydro (water is pumped up a hill during the day, and allowed to flow through turbines at night to generate electricity) or compressed air storage (air is compressed into large salt caverns and then allowed to expand over a turbine to generate electricity).

Electrical vehicles (EV) provide an interesting solution to the problem of electrical grid storage. An EV does not necessarily reduce emissions if you use coal-fired or natural gas power to charge it, but EVs do provide a large network of storage capacity. If EVs become more common, they will provide a large steady source of night-time demand, allowing utilities to avoid ramping-down at night when demand is usually low. Secondly, if the utilities are able to use the electricity stored in the EV when they please, they can better meet variable and peak demand. Although there are significant limitations in battery technology which limit mass proliferation of EVs, an EV future is an exciting opportunity to move towards a more effective and better-managed grid.