RENEWABLES, NUCLEAR OR BICYCLES?
Want to Reduce CO2 by 35%? Ride a Bicycle…Or, Build a Nuclear Power Plant.
It’s commonly reported that electricity production is the largest source of CO2 in the U.S. That’s barely the case.
In 2013, the U.S. emitted 5,278 mmtons of CO2. A breakdown of CO2 emissions per sector (Table 1) indicates that the transportation sector contributed 1,740 mmtons of CO2 (33% of U.S. total) while electric power contributed 2,022 mmtons (38.3% of U.S. total). The most recent data from the U.S. Energy Information Administration indicate that in 2015 the U.S. emitted 5,271 mmtons of CO2. Of this, the transportation sector contributed 1,869 mmtons (35.5% of U.S. total) while the electric power sector contributed 1,925 mmtons (36.5% of the U.S. total). Recent emission trends have been up for the transportation sector and down for the power sector (Figure 1).
Table 1. Energy consumption and CO2 emissions by sector in the U.S. for 2013. Since each sector consumes primary energy indirectly via electric power, consumption data for residential, commercial, industrial and transportation sectors are reported in terms of primary (direct energy consumption), electric power, and total. Emissions data and % share reflect only emissions from direct consumption. Data Source: US Energy Information Administration.
Based on these data, the U.S. could reduce its CO2 emissions about 35% by displacing fossil fuels from either the power generation sector or the transportation sector. That’s easier said than done, but here are three options.
Option #1: Renewables
Currently, the regulatory pressure is being applied to the electric power sector to reduce emissions through the integration of more renewables, with some proposals suggesting that the entire electric grid could be switched over to 100% renewables. As for the transportation sector, eliminating fossil fuels would require that vehicles switch over to electric power that isn’t generated by coal or natural gas, which means renewables or nuclear. Interestingly, in both circumstances the renewables option revolves around the need for improved and affordable energy storage technology; that is, batteries. For the power generation sector large-scale energy storage would be critical when renewable energy supply exceeds societal demand and when societal demand exceeds supply, thus providing dispatchability needs. For the transportation sector, batteries govern the critical feature of electric vehicles; that being mileage range. In addition, there is the need for constructing the necessary infrastructure throughout the U.S. to support re-charging. A 100% renewables option has numerous unknowns as it would require systemic changes to the very nature of U.S. industry and everyday life and would shift electric power and transportation into a dependency on intermittent energy resources—an operational space that is entirely unprecedented in the industrial age.
Option #2: Nuclear
The Federal Highway Administration reported that there were about 113 million automobiles on the road in 2014, which doesn’t account for buses, trucks and motorcycles. Based on an average electric vehicle demand of 0.32 kWhr/mile (Royal Academy of Engineering) driven an average of 15,000 miles/year, a very rough, back-of-the-envelope calculation indicates that a single 1,000-MW nuclear plant operating at an ACF of 0.92 can generate enough electricity (8,059,000 MWhrs) to support 1,669,329 vehicles. Extending this to the entire U.S. population means that 68 nuclear power plants, each with a capacity of 1,000-MW, could support the full 113 million automobiles registered to U.S. citizens. This isn’t exactly in the hands of the American citizenry because it would require regulatory approval and significant public acceptance to make such a move. But, the technology works, it’s feasible, proven, the grid would remain stable, and the logistics are more manageable than those associated with shifting the energy source of the entire U.S. power grid to renewables. Again, these calculations are offered as a means for making a broader point and are not presented as a thorough analysis.
Option #3: Bicycles
A third option would significantly reduce emissions and it’s completely within our control—bicycles. Practically every home in America has one and everyone in America grew up riding one. Moreover, they’re affordable and low-maintenance and we could begin implementation tomorrow. But, not very likely is it? And why not? Could it be that we would rather shift the burden of solving our biggest problems to someone else? Could it be that we aren’t willing to make a real, substantive individual sacrifice to reduce emissions? Of course, I ask these questions tongue-in-cheek only to highlight some hypocrisy on our part (as for myself, I wouldn’t turn in my truck keys). Why is it that we choose to focus regulatory pressure on the power sector to implement a systemic change that is full of unknowns, logistically very difficult and would require significant investment and long-term planning with unprecedented outcomes, yet it is completely within our own power to accomplish similar results simply by parking our cars and riding a bike? First, we’re accustomed to the independence and autonomy that vehicles afford us as they’re available whenever we need them and we’re not prepared to give up those benefits. Moreover, making such a systemic shift from cars to bicycles would be too hard, too much of a burden, it would disrupt our lives, and it’s impractical. In addition, it wouldn’t be safe or reliable and many people in our society simply wouldn’t be able to do it; not to mention the problems we would face in inclement weather. Coincidentally, we hear similar arguments from the power generation sector regarding the shift to renewable energy—i.e., reliability, pragmatics, unknowns, weather, etc. But, when we hear this from the electric power sector, we generally scoff at them for being entrenched in an outdated model and unwilling to change.
A check list of important metrics summarizes the benefits and concerns with each of the three options. All three are clean and safe, but when it comes to assessing which options are reliable, affordable, feasible, practical, and proven and offer grid stability, bicycles and renewables fade away. Only nuclear can deliver on all counts with the exception being that additional analysis would be required as pertains to economics and water consumption.
This analysis may come across as a bit sarcastic, but that’s not the intention. If we as a society are expecting the power sector to consider systemic, unproven and unprecedented changes to what is arguably the single most critical industry in our economy, then it’s only fair that we look in the mirror and expect some serious, systemic changes from ourselves…then we need to go look in the garage and get out that bicycle.
As for me and my house, we’re looking to nuclear.
~ david gattie