Many anecdotes are told about engineers, some more successful, some less so. I recently read one of these jokes which gave me the idea for my intervention today.

An electrical engineering professor spoke to students about the differences between engineers and academics, explaining that:

Both engineers and scientists want to understand the world and solve problems. Engineers worry about how much something costs. College students don’t worry about costs; they just want to know the truth. Therefore, the difference between an engineer and an academician is that an engineer has at least an iota of common sense.

Having analyzed better the content of this difference, we can notice, for example, that in the case of energy supply systems, this “drop of common sense” becomes extremely noticeable and important. Theoretical scientists (researchers, teachers, scientists) can approach the energy network with some detachment, but practical engineers must keep it running 24/7. Problem-solving engineers are directly involved in the activity and usually face the consequences of technological and human errors and shortcomings, whereas scientists and, unfortunately, many politicians are more insulated and protected from unpleasant consequences. This distinction was perfectly noted by Thomas Sowell: It’s hard to imagine a more stupid or dangerous way to make decisions than to put those decisions in the hands of people who pay nothing for mistakes.

As a hybrid engineer-turned-university-professor, I thought there was some truth in the joke when two categories of specialists discuss the replacement of classical modes of transport based on fossil fuels with others that run on electricity, preferably “green”. The reasons for the replacement were revealed by university scientists: emissions of CO2 and other gases affect the global temperature and air quality in places of heavy traffic.

Engineers do not deny the truth of academic theorists. They need to find the practical solutions needed for land, air and sea transport in the next few years to use electricity instead of petrol, diesel, kerosene or fuel oil as an energy source. And here comes the problem, which I will illustrate using published US data. To the extent that there is comparative data in Romania as well, the solution to the problem can also be solved there.

Electrification of transport is considered by American scientists as a universal and integral avalanche for reducing CO2 emissions. But if the entire fleet is converted to electric cars, where will the necessary electricity come from? That’s the question.

In 2022, according to Reuters, electric cars in America accounted for a tiny share – less than 1% of the total 250 mln passenger cars, SUVs and vans. But the situation will radically change, if you believe what he published Thursdayd The Wall Street Journal January 1, 2023: The transition to electric cars triggers the biggest auto factory construction boom in decades:

According to the Center for Automotive Research, a Michigan-based nonprofit, about $33 billion in new investment in auto plants was earmarked in the U.S. through November, including money to build new assembly plants and battery factories.

…

According to the consulting company AlixPartners, by 2026 the global automotive industry plans to spend 526 billion dollars on electric vehicles.

Major car manufacturers have expressed confidence in the electric future of their products. This, for example, is eloquently stated by General Motors climate change is real and we want to be part of the solution by putting everyone in an electric car (until 2035). And Ford adds: We will lead America’s transition to electric vehicles (50% by 2030).

About pure, hybrid or electric vehicles (EV), I have written several articles on this platform: Electric car = car of the future? Pros and cons, electric cars and their dependence on big oil, Tesla Altruist vs. Tesla Egoist and the Parable of the Good Samaritan, Transition to 100% “green” energies – an exercise in magical thinking. Do we need evolution or revolution?. We have analyzed their advantages and disadvantages, primarily in terms of the many types of minerals and mining activities required to extract the metals and non-metals that make up BATTERY – a real Achilles heel for “green” or “renewable” electricity (Green energy storage – Achilles heel for Net Zero policy)

I put “green” and “renewable” in quotation marks because neither solar nor wind energy are actually green and renewable. The fuels they use, solar and wind, are environmentally friendly and renewable, but solar and wind systems, by design and environmental impact, are neither environmentally friendly nor renewable.

Let’s put aside the questions about the batteries (hundreds of millions!) that will need to be made for the electric cars of the “zero emission future” and try to estimate the amount of “green” electricity needed to power those cars.

I begin with a chart published by the Energy Information Administration (EIA) that shows the distribution of total US energy in 2021 by sources of production and sectors of consumption (Figure 1). For 2022, a similar schedule was not published.

It is worth highlighting a few key figures from this graph:

– In 2021, the United States consumed 73.5 quadrillion Btu (21,541 TWh) of total energy.

– Of this amount, 12.9 quadrillion Btu (3,781 TWh) was electricity, representing 17.6% of total consumption.

– Almost all electricity was consumed in the industrial, residential and commercial sectors. The transport consumed a very small amount of electricity (less than 1%).

– On the other hand, the transportation sector consumed 26.9 quadrillion Btu (7,884 TWh) of non-electric energy. This figure is 37% of the total energy consumption more than twice of electricity consumed in all other sectors.

Since the transport sector includes all land, air and sea vehicles, and since electrification will be limited to land vehicles in the near future, it is necessary to estimate the amount of energy consumed only by cars, SUVs and vans. Electric trains and trucks are not considered yet.

Document published in 2021 Oak Ridge National Laboratory (part of the Department of Energy) declares: (1) In 2020, oil accounted for 90% of US transportation energy consumption and (2) In 2018, cars and trucks accounted for 62% of US transportation oil consumption.

In the absence of recent data, assume these percentages remain in 2021. A simple calculation shows that cars and trucks consumed 26.9 x 0.9 x 0.62 = 15.0 quadrillion Btu (4,398 TWh) of gasoline or diesel in in 2021. Fossil fuel energy consumption simply for ground transportation in the US exceeded the entire amount of electricity produced in 2021.

The first preliminary conclusion: Converting all cars and trucks to electric vehicles would double America’s national electricity generation system, along with all that that means: green sources, power lines, gas stations.

But the situation described above requires taking into account additional factors for which there are no “hard data”, but only some approximations:

– The efficiency of electric cars is ~85-90% in the transformation of electrical energy into the energy of the car’s movement. Internal combustion engines have an efficiency of only 15-25%.

– Electric batteries lose approximately 15% of their stored energy during the charge-discharge interval.

– According to the schedule in fig. 1, the output of electricity at the power plant is 35%, the rest is various losses, including from transmission lines.

And now let’s solve a simple arithmetic problem.

a) An internal combustion engine car that has 10 Btu (3 Wh) of energy in the tank in the form of gasoline will use about 2 Btu for the trip.

b) An EV using the same 10 Btu of fuel will have 10 x 0.35 = 3.5 Btu of energy available, 3.5 Btu x 0.83 = 3.0 Btu of electricity in the battery after charge/discharge losses and finally , 3.0 x 0.87 = 2.6 Btu of travel energy.

It turns out that an electric car can run on about ¾ (2:2.6) the number of Btu consumed by an internal combustion vehicle. It also implies that instead of consuming 15 quadrillion Btu per year for the modern US car fleet, we could theoretical let’s reduce that amount to 11.25 quadrillion Btu to produce 11.25 x 0.35 = 3.93 quadrillion Btu (1152 TWh) of electricity for the future car fleet.

The second preliminary conclusion: returning to the data in fig. 1, electricity production in 2021 was 12.9 quadrillion Btu. The 3.93 quadrillion Btu of additional energy needed for a “zero-emissions future” would represent an excess of approximately 30.5% over the current capacity of the US power system for generating electricity.

What energy plan does the US Department of Energy currently have to address this problem? A possible answer can be obtained by considering fig. 2, another graph produced by the EIA showing the government’s projections for the increase in electricity generation capacity until 2050, when Net Zero policies will be implemented and mean the (almost) complete elimination of fossil fuels as an energy source.

After the post-pandemic recovery of electricity production, the increase in production until 2050 is 1% for all three economic growth scenarios (high, low, regular. We immediately note that these increases also cover the sectors of industry, population, trade, New opportunities are likely to use energy wind and sun, which means that the batteries of the car fleet in the “zero-emission future” will not be able to charge unless the sun is shining in the sky or the wind is blowing.

And where will the surplus of 30% of the additional electricity needed for the electrification of all ground vehicles (excluding air and sea) come from? And even if this additional generating capacity is added, how much will it cost and who will pay to re-electrify America?

Who could answer better, practical engineers or theoretical scientists?

A possible answer was found in the meta-study Review on 100% Renewable Energy System Analyzes—A Bibliometric Perspective, published in November 2022. The authors bibliometrically analyzed more than 600 scientific articles in which 100% renewable energy systems were discussed in the context of growing concerns about climate change and global warming caused by human activities and the use of fossil fuels. The authors noted an impressive increase in the number of scientists and scientific publications related to the transition to net zero. Starting from scratch around 2010, in 11 years it has reached 1,400 university authors, accumulating almost 36,000 citations to their articles. Read the full article and comment on Contributors.ro