Two forces drive a need to transition off fossil fuels – climate change and depletable resources. Deniers and politicians (often the same thing) want to kick the can down the road, either to avoid being blamed for the pain of transition or in the hope that a silver bullet will be discovered in the future. Or, they just can’t read the writing on the wall.
Like it or not, the plan described below is where we must be some day. We have a choice, however, for how to embrace it – determined leadership for an organized transition, or haphazard foot dragging with incremental changes while mopping up the problems that delay will cause. Delay undoubtedly will make a transition more expensive (e.g., building higher sea walls) and more painful. Worse, it might ruin everything. We should get started today.
So, what’s it going to take to make energy sustainable and to save the planet? Basically, replace fossil fuels and sequester as much carbon as possible. The key is generally to convert everything to electricity, since electricity can be generated without fossil fuels while being transmissible and storable. The plan is described below, but first is a reference table of 2019 US energy use that can be derived from the underlying factual information presented after the plan description.
| Current Fossil Derived Energy* | Plus Current Electricity Use | |
| Transportation | 28 | negligible |
| Industrial | 26.4 | 6.6 |
| Commercial | 4.7 | 13.3 |
| Residential | 7 | 14 |
*Quadrillion BTU/yr (Quads or Q) – US Total = 100 Q
- Electricity (34Q) – replace all fossil generation with a combination of solar, wind, and nuclear. This will require 7 trillion new Kwhr (including accounting for system losses of about 3%) in the form of centralized sources (e.g., power plants converted to wind, solar, and nuclear) and additional distributed sources (e.g., rooftop solar cells), averting 1.5 billion tons/yr of greenhouse gas (in 2019, the US emitted 6.7 billion tons/yr).
- Transportation (28Q) – replace land transport fossil with electric –equivalent to 6 trillion Kwhr of new, non-fossil electric generation, averting 1.3 billion tons/yr of greenhouse gas. Tolerate, until there is a technical solution, fossil-fueled air and marine transport –equivalent to 1.4 billion barrels of oil (the US currently uses 18 billion barrels/yr), which will continue to emit 0.5 billion tons of greenhouse gas. But offset this continuing emitted carbon with sequestration.
- Industrial (33Q) – Most industrial energy is used to generate what is called “process heat” (e.g., boilers, melting, etc.), leaving only about 5% for space heating. Some process heat is already generated from electricity (e.g., aluminum smelting), so assume 20% of total industrial energy is from electricity, which was converted to non-fossil as described above. By 2040, retrofit half of the current 80% of now fossil energy to electricity or onsite renewables, leaving 40% of industrial energy as fossil with its greenhouse gas sequestered.
- Commercial (18Q) – 25% of commercial energy is for space heating. Assume half of that is electric HVAC, leaving commercial’s fossil use as 12.5% of its total energy use. The remaining 87.5% is electric, which was converted to non-fossil as described above. By 2040, convert half of the fossil heating to non-fossil leaving the rest as fossil with greenhouse gas sequestration.
- Residential (21Q) – 43% of residential energy is for space heating. Assume 35% is fossil-fueled with the balance (e.g., air conditioning) using electricity. That means residential energy is 65% electricity, which was converted to non-fossil as described above. By 2040, convert half of fossil heating to non-fossil, leaving the rest as fossil with greenhouse gas sequestration.
- (“Industry” is things like factories, while “commercial” is things like office buildings and malls. Most of industrial energy is for what is called “process heat” for manufacturing, whereas much of commercial energy is for lighting and things other than HVAC.)
This plan requires about 18.4 trillion Kwhr of new electricity and, by 2040, averts 4.4 billion tons/yr of greenhouse gas. After 2040, about 2.6 billion tons/yr of greenhouse gas will still be emitted until we can figure out how to wean the rest off fossil fuels and fix agriculture. Thus, by 2040, the plan would eliminate all but about 4 billion barrels of oil burned per year and reduce greenhouse gas emissions by 60%. A table summarizing this plan is presented at the end. A very simplified estimate of what the plan will cost is:
- New electricity – $11.6 trillion capital cost (about half of US GDP), based on a recently installed Japanese large solar array described below, assuming 1 Kw of installed renewable capacity will generate 1,000 Kwh/yr.
- Carbon sequestration – $170 billion/yr, based on an optimistic cost estimate of $100/ton to address the 1.7 billion tons/yr remaining after 2040. This is about 25% of the US defense budget). More could be spent if we also deal with the ramp-down period. Note that “sequestration” is still a vague term due to the current nascence of its technology.
The technologies for electric generation conversion are available today. Carbon sequestration technology still has development challenges, but from current descriptions, they don’t appear to be insurmountable. Retrofitting space heating and some of industrial process heat will require some innovation or clever adaptation of existing technology. Conversion of the entire land transportation fleet to electricity will require storage battery improvements and a new infrastructure for “fueling.” More nuclear for the electric conversion is advisable, but fuel waste storage is an issue to be solved. The US already spent billions studying Yucca Mountain (Nevada) for this, which is an excellent site with transport designed to withstand a locomotive crash, but NIMBY politics killed it.
Further thought will likely cause tweaks to the plan, its reduced factual data, and to the table at the end. For example, the table lists zeros for current non-fossil energy use in several sectors, but that is not exactly true. These adjustments are likely to be relatively minor, however, and are not expected to change the design or feasibility of the presented plan.
Economists should have a ball with these numbers. First, they mix capital and operating costs, and it is not simple to separate the two. Solar electricity should be low on operating costs, but far from zero and current descriptions are vague, while the sequestration operating cost must already have capital amortization built into it, given the way current costs of the technology are described. Furthermore, the costs presented above are not unique, meaning that some of this money would be spent anyway on fossil technology. For example, replacement costs for current fossil technology could be replaced with some of the renewables’ conversion cost. The time value of money needs considering for this 20 year transition and for renewables operating costs. Optimization also needs considering. For example, the simplified cost estimate simply scaled up one solar example in Japan for electricity conversion, but in reality, the conversion will consist of some optimized combination of wind, nuclear, solar, and centralized/distributed systems. In addition, there will be many costs of associated adaptation technology. For example, all those electric vehicles need to be developed/manufactured along with better storage technology, not to mention the technical challenges remaining for carbon sequestration. There are also issues of how to pay for this. For example, carbon sequestration can be paid for by a carbon tax, but such a tax will likely be passed on to consumers. There are also pragmatic issues like where to put all those solar cells.
Undoubtedly, there are many more economic considerations as well as many technology ones, not to mention societal and even political considerations. The important issue, however, is that these numbers, although they might be painful, are not prohibitive and the technology is feasible and to a large degree already available. There is no need to wait for a silver bullet that is unlikely to materialize.
The transition period, 20 years, is also feasible, and it is convenient considering that much of the fossil technology to be replaced will be due for rebuilding during that time period anyway.
There is no question that spending half of GDP on a new infrastructure and about a quarter of the defense budget equivalent on ongoing sequestration will be disruptive. But will it be more disruptive than Climate Change?
The facts underlying the plan numbers presented above are (recent US figures unless noted otherwise; all web references were accessed on October 27, 2020; many numbers are rounded):
- The US
uses 100 quadrillion BTUs/yr (Quads)[1]. This is equivalent to 18 billion barrels of
oil[2] (49 million barrels a day). The US consumes 17% of the world’s energy1.
- 1 Quad = 300 billion Kwhr = 180 million barrels of oil = 39 million tons of coal = 1 trillion cu ft of gas (approximately)2
- Energy is supplied
by the following fuels: 37% petroleum,
32% natural gas, 11% coal, 8% nuclear, and 11% renewables.[3]
- The renewables breakdown is about 27% wind, 25% hydro, 23% biofuels, 20% wood, 10% solar, 4% waste, and 2% geothermal.[4]
- The US uses 140 billion gallons/yr of gasoline.[5]
- Primary fuel use by sector is: 37% electricity, 28% transportation, 23% industry, 7% residential, and 5% commercial.[6]
- Total energy
(primary fuels plus electricity) by sector is: 28% transportation, 33% industry,
21% residential, 18% commercial, with the last 3 using a combination of fuels
and 40% of all electricity generated.
Fossil fuel supplies nearly all of transportation energy needs.[7]
- Worldwide, transportation breaks down approximately as follows: 50% cars/buses, 12% trucks, 13% marine, 10% air, 15% other (e.g., rail, pipelines).[8] Given the US love of cars and trucks and its global trade, the following is assumed for the US: 70% land, 15% marine, 12% air, and 3% other.
- The fraction of total energy used by each sector that is electricity is: Commercial is 74%; Residential is 67%, Industrial is 13%, and Transportation is negligible.[9]
- 37% of US
primary fuels make electricity. Electricity
is a “secondary” energy source because it is generated from primary fuels.[10]
- Electricity is generated from the following primary fuels: 38% natural gas, 24% coal, 20% nuclear, and 18% renewables, and 0.5% petroleum.[11]
- There are currently 98 nuclear power plants in the US.
- US utility generation is about 4 trillion Kwh/yr. That is about 460 – 1Gw power plants (a typical modern plant size), if they ran at full capacity (they don’t).
- A modern wind turbine has about a 2 MW capacity and can be expected to generate about 4 million Kwhr/yr.[12]
- A nuclear power plant costs about $10 billion for about 1 Gw capacity.[13]
- A 1 Gw power plant running at full capacity 24 hrs/day, 365 days/yr will generate 9 billion Kwh/yr.
- A 12 Kw capacity solar array might be expected to generate about 12,000 Kwh/yr, depending on location.[14]
- 43% of
residential energy use is for space heating/cooling (there are 110 million
homes). [15] That is about 9 Quads. It is unclear how much of residential space
heating is electric HVAC. Assuming it is
20% would mean fossil residential space heating is 7.2 Quads, equivalent to,
generating 0.5 billion tons/yr of greenhouse gas.
- New home construction is around 1.4 million houses per year.[16]
- 25% of
commercial energy use is for space heating/cooling. [17] That is 2.4 Quads, but again, the electric
fraction is unknown. Assuming it is
higher than residential, 50%, fossil based commercial heating/cooling would be
1.2 Quads, equivalent to about 0.1 billion tons/yr of greenhouse gas.
- There are 6 million commercial buildings in the US with 90 billion sq ft of floorspace.[18]
- The majority of industrial energy use is for “process heat”. Assume that fossil-based space heating uses only about 5% of industrial energy (1.6 Quads, 0.1 billion tons/yr).
- Declining renewables costs, especially wind and solar, are making them competitive with traditional energy sources. Wind energy costs about $0.06/Kwh (3-12 cents range)[19] (US average electric bill is $0.12/Kwh); a 2 MW turbine (enough for 200 houses) costs about $4 million to install[20]; solar installation costs about $40,000 for 12 Kw of capacity[21] (enough for a typical house); Japan installed a large, 70 MW, solar array on 0.5 acres at a capital cost of $44 million[22]. Geothermal heating is equivocal – expensive to install (about $30,000 per home), expensive to run (electricity), but still perhaps 30% cheaper to run than burning fossil fuel. Biofuels are also equivocal – somewhat carbon neutral, but expensive to grow abundantly/quickly (e.g., algae and sugarcane) and to process into fuel.
- The US emitted
6.7 billion tons of carbon dioxide equivalents (greenhouse gases)[23] in 2018. According to the use sector breakdown above,
this is 1.5 billion tons/yr from electricity generation (less renewables and
nuclear), 1.9 billion tons/yr from transportation, 1.9 billion tons/yr from
industry, 0.5 billion tons/yr from non-electric residential space heating, and perhaps 0.3 billion tons/yr from commercial
(difficult to know how much is electric HVAC).
Agriculture is about 20% of the total, about 0.6 billion tons/yr.
- Renewables are not unscathed in this consideration. For example, decaying vegetation in hydropower reservoirs is a notorious greenhouse gas emitter.
- Carbon sequestration from the atmosphere currently costs about $600/ton with nascent technologies. Optimists in the field are hoping for $100/ton.[24]
Although these are useful facts, there are tricky overlaps, mainly because sectors use both primary fuels and electricity. Here are some manipulations of those US facts sorting out the overlaps and complications:
- Electricity – deducting renewables and nuclear, the remaining fossil-based generation totals 23 Quads (7 trillion Kwhr) and emits 1.5 billion tons/yr of greenhouse gas. (Remember, some additional greenhouse gas is also generated from renewables.)
- Transportation – ground-based vehicles (cars, trucks, and buses) use 20 Quads and thus emit 1.3 billion tons/yr of greenhouse gas. air – 3.4 Quads, 0.23 billion tons/yr; marine – 4.2 Quads, 0.3 billion tons/yr; with about 0.6 Quad (0.01 billion tons/yr of greenhouse gas) remaining for things like railroads.
- Space heating – Residential, commercial, and industry account for about 10 Quads and thus 0.7 billion tons/yr of greenhouse gas.
Of the 2.6 billion tons/yr of greenhouse gas emissions remaining, about 1.5
billion tons/yr is from industrial processes, 0.7 is from agriculture and the
rest, 0.4, must be from all other sources and rounding.
Sustainable Energy Plan Accounting
| Energy | Greenhouse Gas Emissions | |
| Electric | ||
| Current Fossil Use | 23 Q* | 1.54 Billion Tons/yr |
| Non-fossil | 14 Q | 0 |
| Convert to Non-fossil | 23Q = 7 TKwh** | -1.54 |
| Remaining after 2040 | 37 TKwh non fossil | 0 |
| Transportation | ||
| Current Fossil Use | 28 Q | 1.88 |
| Non-fossil*** | 0 | 0 |
| Convert to Non-fossil | 20 Q = 6 TKwh | -1.34 |
| Remaining after 2040 | 8 Q | 0.54 |
| Industrial | ||
| Current Fossil Use | 26.4 Q | 1.77 |
| Non-fossil | 0 | 0 |
| Convert to Non-fossil | 13.2 Q = 4 TKwh | -0.88 |
| Remaining after 2040 | 13.2 Q | 0.88 |
| Commercial | ||
| Current Fossil Use | 4.7 Q | 0.31 |
| Non-fossil | 0 | 0 |
| Convert to Non-fossil | 1.1 Q = 0.3 TKwh | -0.1 |
| Remaining after 2040 | 1.1 Q | 0.1 |
| Residential | ||
| Current Fossil | 7 Q | 0.47 |
| Non-fossil | 0 | 0 |
| Convert to Non-fossil | 3.7 Q = 1.1 TKwh | -0.25 |
| Remaining after 2040 | 3.7 Q | 0.25 |
| TOTAL New Electricity | 17.1 TKwh | |
| TOTAL Remaining GH Gas | 1.72 BTY |
- Quadrillion BTU/yr (Quads). Note that 37Q of electricity is generated but there are system losses.
** Trillion Kilowatt hours/yr
*** “Non-fossil” means within the sector
and does not mean any non-fossil component in electricity used
[1] https://www.eia.gov/tools/faqs/faq.php?id=87&t=1#:~:text=In%202017%2C%20U.S.%20total%20primary,of%20about%20582%20quadrillion%20Btu.
[2] https://www.britannica.com/science/quad
[3] https://www.eia.gov/energyexplained/us-energy-facts/
[4] http://css.umich.edu/factsheets/us-renewable-energy-factsheet
[5] https://www.eia.gov/tools/faqs/faq.php?id=23&t=10#:~:text=In%202019%2C%20about%20142.71%20billion,9.31%20million%20barrels)%20per%20day.&text=There%20are%2042%20U.S.%20gallons%20in%20a%20barrel.
[6] https://www.eia.gov/energyexplained/us-energy-facts/
[7] https://www.eia.gov/totalenergy/data/monthly/pdf/sec2_3.pdf
[8] https://www.maritime-executive.com/article/transport-uses-25-percent-of-world-energy
[9] https://www.eia.gov/totalenergy/data/monthly/pdf/sec2_3.pdf
[10] https://www.eia.gov/energyexplained/electricity/use-of-electricity.php
[11] https://www.eia.gov/tools/faqs/faq.php?id=427&t=3
[12] https://www.wind-watch.org/faq-output.php#:~:text=What%20is%20the%20power%20capacity,range%20of%202%2D3%20MW.
[13] https://www.synapse-energy.com/sites/default/files/SynapsePaper.2008-07.0.Nuclear-Plant-Construction-Costs.A0022_0.pdf
[14] https://news.energysage.com/how-much-does-the-average-solar-panel-installation-cost-in-the-u-s/
[15] http://large.stanford.edu/courses/2010/ph240/hamman2/
[16] https://www.census.gov/construction/nrc/pdf/newresconst.pdf
[17] https://solarfeeds.com/residential-vs-commercial-energy-use/#:~:text=Commercial%20Energy%20Use%200&text=Combined%2C%20buildings%20in%20the%20United,consume%2040%25%20of%20all%20energy.&text=2)%20In%20terms%20of%20energy,energy%20as%20the%20commercial%20sector.
[18] http://css.umich.edu/factsheets/commercial-buildings-factsheet#:~:text=In%20the%20U.S.%2C%205.6%20million,in%20floor%20space%20since%201979.&text=By%202050%2C%20commercial%20building%20floor,a%2034%25%20increase%20from%202019.
[19] https://www.irena.org/costs/Power-Generation-Costs/Wind-Power
[20] http://www.windustry.org/how_much_do_wind_turbines_cost#:~:text=The%20costs%20for%20a%20utility,%243%2D%244%20million%20installed.
[21] https://news.energysage.com/how-much-does-the-average-solar-panel-installation-cost-in-the-u-s/
[22] “KYOCERA Starts Operation of 70MW Solar Power Plant, the Largest in Japan,” Kyocera website (November 5, 2013), accessed December
22, 2015, at: http://global.kyocera.com/news/2013/1101_nnms.html
[23] https://www.epa.gov/ghgemissions/inventory-us-greenhouse-gas-emissions-and-sinks
[24] https://www.sciencemag.org/news/2018/06/cost-plunges-capturing-carbon-dioxide-air