Goehring & Rozencwajg, Natural Resource Investors, discuss why they believe oil demand will remain vital for many years.
blog.gorozen.com
Most articles list EVs as anywhere between two and three times more energy efficient than the ICEs they replace.
The basis for this claim is that internal combustion engines are only 40% efficient and that nearly 60% of the energy contained in gasoline or diesel fuel is “wasted,” –mainly in the form of heat and friction. On the other hand, an electric motor transfers nearly 90% of its electrical energy directly to the wheels. The difference leads many to erroneously conclude that an EV is almost three times as “efficient” as an ICE.
This common argument is fundamentally flawed for three reasons.
First, it fails to capture the energy needed to make the battery;
second, it fails to distinguish between thermal and electric energy;
and third, it fails to account for the poor energy efficiency of renewable energy.
An EV uses 32 kWh of electricity per 100 miles traveled. The vehicle’s battery, meanwhile, consumes an incredible 24 MWh in its manufacturing. Assuming a useful life of 120,000 miles, the battery pack consumes 20 kWh per 100 miles traveled, two-thirds as much as the direct electricity itself. Most analysts we have read fail to include this onerous energy burden when touting the EV’s superior efficiency.
Next, most efficiency arguments fail to distinguish between thermal and electrical energy.
While most of us have been taught that energy is fungible, several distinct forms of energy have differing degrees of usefulness. Although it is beyond the scope of this essay, the distinction surrounds the randomness, or entropy, of the energy carrier. The more entropic an energy source, the less useful work it can perform. Burning fuels of any kind always has high entropy. Electricity, on the other hand, with its orderly string of moving electrons, has extremely low entropy.
Upgrading from thermal to electric energy always introduces predictable inefficiencies based on the fundamental laws of thermodynamics.
When pundits claim an EV is three times more efficient than an ICE, they fail to make this distinction. In a combustion engine, the driver converts gasoline (high entropy) into forward motion with approximately 40% efficiency. Electricity (low entropy) drives a motor with approximately 90% efficiency in an electric vehicle. However, electricity does not exist in nature but instead must be generated. Burning natural gas (high entropy) to generate electricity (low entropy) is only 40-50% efficient. The EV is not inherently more efficient; instead, the inefficient “upgrade” from thermal to electric energy occurs off-stage and is conveniently omitted by most analysts.
Last, most efficiency arguments fail to account for energy generation in the first place.
For example, as we saw with Norway, the only way to lower automotive carbon emissions is by converting to renewable energy for both the manufacturing and powering of the vehicle. Unfortunately, renewable power is prohibitively inefficient. This may be surprising. After all, neither wind nor solar “burn” fuel, and so are not subjected to the inefficiency of moving from thermal to electric energy discussed earlier. However, wind and solar suffer from incredibly low energy density (consider the heat from a gas stove compared to a stiff breeze). To capture useful quantities of power, windmills must stand 300 m tall, and solar farms must spread out over thousands of acres. These large installations require raw materials like steel, cement, copper, silver, and polysilicon. These materials, in turn, consume vast quantities of energy to both mine and process. By comparison, oil and gas extraction is highly efficient.
We study the total energy required to produce various forms of energy, a metric known as energy return on investment (EROI). While a single unit of invested energy might generate fifty units of (thermal) energy over the life of a productive oil well, it will only generate ten units of (electrical) energy with wind or less than six from a solar panel. Furthermore, wind and solar power must be buffered by grid-level battery storage to avoid intermittency, which requires far more energy. Fully buffered wind likely has an EROI of six to seven, while solar may be as low as three. Claiming a renewable-powered EV is efficient because its motor operates at 90% fails to account for the poor upstream efficiency.
instead, we have taken a completely different approach when calculating automotive efficiency: assuming 100 kWh of available thermal energy, how far can a driver expect to travel in an ICE compared with an EV. We prefer this methodology, as it aligns with our intuitive understanding of “efficiency:”: how much can we get out of a single unit of energy. Using this approach, the race isn’t even close --the ICE wins “hands down.”
An efficient ICE can expect to achieve 37 miles per gallon of gasoline or 98 kWh of thermal energy per 100 miles. The vehicle components require 20 MWh, or 15 kWh per 100 miles, when amortized over a useful life of 170,000 miles—according to Argon Labs. The ICE can expect to consume 112 kWh per 100 miles, of which 90% represents thermal energy in the form of gasoline. Oil extraction benefits from a very high EROI of 60:1 at the wellhead. In other words, 60 units of thermal energy, in the form of crude, comes up the wellbore for every unit of energy invested. Transportation and refining consume approximately 15% of the energy contained in the crude, lowering the EROI to 50. To be conservative, we are assuming an ultimate EROI of 45. Therefore, investing one kWh of thermal energy will create 45 kWh of thermal energy, propelling the ICE 41 miles.
A modern EV consumes 32 kWh of direct electrical energy per 100 miles. The battery requires an additional 24 MWh, which over the vehicle’s useful life of 120,000 miles equals 20 kWh per 100 miles. The remaining vehicle components consume 27 kWh per 100 miles. The EV can expect to consume 80 kWh per 100 miles, of which 95% is electricity.
Assuming the electricity is generated in a natural gas-fired power plant, the EROI is approximately 25 once transmission line losses are considered. Starting again with one kWh of thermal energy, we would expect to generate 25 kWh of electricity. The EV would, therefore, travel 32 miles – 20% less than the ICE. If electricity is generated using a mixture of unbuffered wind and solar, the EROI could be as low as 13. Therefore, one kWh of energy would only generate 13 kWh of electricity, propelling the EV a mere 16 miles – over 60% less than the ICE.
Never in history has a less efficient “prime mover” displaced a more efficient one. We believe this time will be no different. While governments may try to coerce drivers into buying EVs or even ban ICE altogether, these policies will ultimately fail as consumers insist on keeping their more efficient vehicles. A new battery breakthrough would help make EVs more energy efficient, and we are studying the space very closely. In particular, we are impressed with the work being done by the team at PureLithium, in which we have made a small private investment.
However, we cannot identify any battery technology that would materially change this analysis. Until then, we expect internal combustion engines will continue to dominate, and EV penetration will disappoint.