written 20 October, 2024
published 27 October, 2024
The current US energy reality is that 79 percent comes from coal, oil, or natural gas, 13 percent comes from real renewables (solar, wind and hydro), and 7 percent comes from nuclear. Electricity from nuclear is the most expensive power on the grid, twice grid scale solar. Today, a typical 1,100MW reactor costs about $30B, in part because they are custom made, increasing the cost. Their size means power production is centralized, needing extensive grid connections. Only two new reactors have come online in the US since the 1979 Three Mile Island event,
While there is a resurgence of big money interest in small modular reactors, with projected capacity of 1MW-300MW, this is still at the concept stage, despite a few holes in the ground for new development facilities. The expectation is that mass produced smaller reactors will be cheaper. However, these won't be in production any sooner than 2030, with no idea of final cost. Consequently, there is no actual market for these reactors right now.
As the climate crisis grows, the need to eliminate further fossil fuel combustion is imperative. But even some people not employed by a fossil fuel company believe there is no practical way to eliminate fossil fuels. Is there any hope? Perhaps.
A Sankey Flowchart is a graphic representation of our total energy system in one visual diagram. The chart breaks energy down into four levels. Primary energy in the original material, such as coal, oil, or natural gas. This is converted into Secondary energy, which is a form that can be transported, such as electricity, gasoline, or diesel. Final energy has been distributed to the end customer, and is applied as Useful energy for the individual need. Every step is inefficient, with some percentage going to "waste", often rejected as heat. The result is that Useful energy is only about 1/3 of the original Primary energy.
For example, when coal (primary) is burned to produce steam, to turn a turbine, which generates electricity (secondary), 65 percent of the energy is already lost. Burning natural gas, the other major source of electrical production, the loss is still 55 percent. Coal and gas plants are large and expensive, lasting about 30 years, getting less efficient as they age. Shutdowns due to regular maintenance, or emergencies, waste energy in the long cool down and heat up phases. As grid load peaks, older, less efficient plants come online. Even though they are used at less than their full capacity, the plants need to be kept hot, and staffed, even if only needed for an hour a day.
Other fossil fuel usage is also inefficient. Natural gas stoves put only 40 percent of the heat into your food, the rest is lost heating the kitchen. In an automobile, as little as 20 percent goes into moving the car, the rest is lost moving various parts, operating accessory items, and most heats the atmosphere. Much of that useful 20 percent is thrown away when you brake the car to a stop.
Real renewables skip the combustion/heat phase entirely, going straight to electricity. Losses from grid transmission, distribution, and battery storage are much less, increasing the percentage of useful energy available.
An induction heated stove uses much less energy to cook the same food. An electric car uses 90% of the electrical energy, providing 3-4 times more milage per unit of energy. In addition, regenerative breaking recaptures some of the energy used to get the car moving, and stores it back into the battery to be used again. Heat pumps heat a building 3-4 times more efficiently, because they simply move the ambient heat in the air, rather than creating it through combustion.
A completely electrified economy would need 40% less total energy than our current economy, and renewables would produce that energy 3 times more efficiently. Completely switching to electricity gives much more bang for the energy buck.
But this requires transforming our entire energy economy. Millions of jobs will be affected, some lost from the old energy technology, and many more added to construct, and install the new systems. Global estimates range up $45T, which is a lot. However, we already pay about $7T per year for fossil fuels. If unaddressed, the climate crisis will cost $180T, and risks putting an end to humanity. The only question is: do we have the wisdom and will to make it happen?
