July 25, 2023

Farming for cars

My dad, an inveterate driver, has made car trips across the width of the United States half a dozen times. At the end of the first day of their first trip, having started out from Boston, he called me and told me, with awe in his voice, that after driving all day they hadn't made it farther than Buffalo. 

Well, it's a big country.

Photo by Don Graham under CC-BY-SA-2.0

The middle of the country is given to mostly one crop: corn. (That's maize to European readers). My mom, who liked to see interesting things on the way, was astounded by just how much land was dedicated to the growing of corn. She was also bored to tears. So on the next trip, she insisted that they go farther south. They never crossed the country as far south as Texas, but all up and down the midwest, they saw a lot of corn.

The US Midwest is blessed with the best farmland in the world, but humans' relationship with it is not that great: that land is regarded as a commodity, and is used for growing commodity crops. Like corn.

Here is a stat that blew my mind when I first heard about it: of the 80 million acres of corn planted in the United States, a lot goes into processed foods, more goes into cattle feed, but the single largest chunk of it, 45 percent, doesn't get eaten at all but goes to the making of corn ethanol. That ethanol is used as an additive to the gasoline you pour into your car's tank.

I am not making this up: it is the United States Department of Agriculture that says 45 percent of the country's corn crop goes into cars' tanks.

Such is the tyranny of the car that not only do people give up huge portions of the public space in cities to it, but also in the United States alone we sacrifice 36 million acres of prime farmland to feed it, or at least the version of the car that needs to burn stuff to move forward.

Which is a crying shame: because internal combustion engines are so incredibly inefficient that two thirds of that corn ethanol just gets wasted as heat. And where I come from there is a word for that kind of wanton waste: it's called a sin.

Think about it: two thirds of that good farm land is wasted. Two thirds of the water to irrigate the corn, thrown away. Two thirds of the fertiliser and the attendant runoff: for nothing. Two thirds of the fossil fuels burned for energy to work the land and process the ethanol: wasted. Speaking of energy: ethanol from corn yields only 1.5 units of ethanol energy for each energy unit used to grow it. Throw away two thirds of that, and you end up with half a unit of ethanol energy, that is, less energy than you put into the process. The word "insane" comes to mind.

The waste of farm land at this scale is the more unwise as extreme weather from human-made climate change makes it that much harder to farm food for people. India has suspended rice exports following catastrophic monsoon rains, even as Indian farmers grow huge amounts of sugarcane for car ethanol.

It doesn't have to be that way.

Imagine that, instead of planting corn, you install solar panels on that land, and used the electricity to power electric cars. An increasing number of people have imagined this, and some have actually done the math to do a miles-per-acre comparison.

The bottom line: An acre of land, if planted with PV solar, could yield 70 times more EV miles than corn ethanol from that same acre powering a combustion engine car. The number varies depending on who is doing the estimating and what assumptions go into their estimate, but a factor 70 is about the median value.

In Brazil and India where they plant sugarcane for car ethanol, the math works out about the same: 70 times more miles per acre if you use the same land for solar energy powering EVs.

This is awesome!

That is, this is awesome from an environmental and climate point of view. But does it make sense for farmers?

A group at UC Davis asked this question, then crunched the numbers. The answer is: Right now, the farmer can make a lot more profit with PV solar on their land, even when you include the installation costs. Farther down the timeline, it's complicated. Whether or not the farmer makes more profit from the solar than the corn depends on the wholesale electricity price, the initial costs to purchase, install, and connect the PV panels, and so on. A price on carbon would tilt the balance away from growing corn for fossil fueled cars. And of course, once everyone drives an EV the demand for corn ethanol would evaporate and its price would go down.

But an early adapter switching from corn to PV solar could really come out ahead. Sweeter yet, they could get into agrivoltaics, where you install PV solar on your land AND plant a crop in between the solar panels. It's like getting two crops from the same land, simultaneously. There is a symbiotic relationship: the presence of the crop cools the surroundings, boosting the PV yield, and the PV array gives partial shade which is beneficial for cooler-climate crops, and conserves water. Some solar panels are raised, and some can be tilted to vertical so that a tractor can access the area in between the panels.

Agrivoltaic vineyard in Laterza, Taranto, Italy. Photo by Emilio Roggero under CC-BY-4.0

Best of all, even when all the EVs in the country are powered off solar PV where ethanol corn used to grow, there will still be plenty of land left. A farmer could choose to diversify their crops, as a hedge against extreme weather events. They could decide to re-wild some of their land and be paid for the carbon capture and ecological services. 

And driving through the Midwest won't be boring any more.

July 22, 2023

Energy efficiency: gasoline, electric, and hydrogen car

Imagine that you bought three pounds of vegetables, and immediately threw out two before starting to cook with the remaining pound.

Crazy, right?

But something like that is exactly what you do every time you put gas into your car's tank: about 70% of the energy in the gasoline gets wasted as heat, and only 30% is put out by the engine to move things.

Where the energy goes in a car, froman interactive graphic at fueleconomy.gov

But it gets worse than that: There are mechanical losses at every step of the drivetrain from things like friction and inefficiencies. So in the end, only 16 - 25 % of the energy you poured into the gas tank goes into moving the wheels, and your car, forward. In the end, it's more like buying five to six pounds of vegetables to end up cooking only one pound.

Sounds like a rip-off to me.

For electric cars or EVs, a large range of efficiencies are quoted, but fuelefficiency.gov says EVs convert over 65 - 69 % of the electrical energy from the grid to power at the wheels, and if you include regenerative braking, where the energy from forward motion gets put back into the battery, that efficiency goes up to 87 - 91 %.

That's more like it!

I get that 9-13% of my vegetables could be peels, stems and other inedible parts, and I can live with not putting those in my cooking.

Incidentally, hydrogen cars are almost as bad as fossil fueled cars, efficiency wise. The electricity to wheels efficiency is only around 34 - 37 %. That's a little better than that of a car with an internal combustion engine, but it really can't compete with the efficiency of a battery EV. And if the hydrogen comes from the cracking of methane (also called "natural" gas) powered by a coal plant, then the hydrogen car is worse than useless from a climate point of view. Did I mention that hydrogen is a corrosive gas that attacks metals and causes cracks? And that it's highly flammable? Hydrogen cars are only a thing in the minds of fossil fuel directors who are hoping to keep selling their fossil gas.

That's why my next car will be an EV.

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June 17, 2023

Battery powered locomotives

California is hard at work cutting carbon emissions. It has heeded the climate warning signs of drought, wildfires, and flash flooding and landslides, and is putting in place a serious climate action plan that reduces fossil fuel use in every sector. For this, it has deployed the California Air Resources Board, or CARB, whose acronym should be revised to "DECARB", as it now includes carbon dioxide and other greenhouse gases into the list of pollutants it needs to fight.

One way CARB is doing that is by telling railroads that starting in 2030 they are no longer allowed to use diesel locomotives that are more than 23 years old. Turning off the dirty diesel locomotives would save Californians $ 32bn in health costs.

You would think that the railroads would come back with a request for a huge chunk of money to help them modernise the rail network, and catch up with everyone else on the planet by making them electric. 

But no. The railroad industry is whining that they are already at work making their operations more climate friendly, that CARB doesn't have jurisdiction over the railroads, and that anyway there's no way battery operated locomotives will be ready by 2030 - because that's the only way they can imagine going electric. And because they are a big industry, the whining is done in a court of law.

I don't know about how railroads claim to be cutting emissions, nor do I know what jurisdictions CARB may or may not have, but I do know that battery operated locomotives are a solution looking for a problem. 

The idea seems to be deployed whenever someone wants to hold on to the past, that mythical and glorious past when a fleet of trains crisscrossed the United States running on coal-powered steam engines, on rails constructed right through indigenous peoples' lands, with total disregard for environmental and territorial issues.

The reason why e-cars and e-bikes need to run on batteries is that they can travel on myriads of roads, streets, alleys, and paths, not to mention off-road. A train however is confined to the rails, and right now there aren't that many of those, so equipping them with overhead wires is eminently doable. To use a battery for something that is catenary-ready is - a solution looking for a problem. 

It would also be an enormous waste of lithium, unconscionable at a time that we need all the lithium we can get to build batteries for those vehicles that are not confined to rails, like e-cars, e-motorcycles, and e-bikes, as fast as we can. For every locomotive battery that carries a whopping 7 MWh of energy, you can build 175 e-car batteries with 40 kWh each, or nearly ten thousand e-bike batteries carrying the typical  750 Wh.

The nation's rail network needs to be upgraded to accommodate high speed trains, and installing overhead wiring would be a relatively small addition to the cost. China is as vast as the United States and for years now they have enjoyed a high speed rail network running on overhead wires, so it's not like it's unproven tech. If you could cover Boston to Washington DC, or St. Louis to Atlanta, or San Francisco to Los Angeles, in three to four hours, you wouldn't take a plane (those are not about to get decarbonised, either, no matter what airline CEOs say).

The US railroad industry's diesel engines are only one step up from the pre-war coal-powered steam engines. It's time for US rail to come into the twenty-first century.

May 18, 2023

Norway's new tack on the EV

For some time now, Norway has been the darling of EV advocates. Article after breathless article will detail how electric cars make up a larger and larger percentage of cars sold in the country. 

But nobody asks how that is done. 
You would think that EV enthusiasts would give a detailed report on HOW the Norwegians got to drive all those EVs, but you would be disappointed. And that's too bad, because Norway is a case study for how to transition to EVs in little more than one car generation.

The recipe is really quite simple: the Norwegian government sweetened the deal for owning an EV so much that if you were sentient at all, you would be gripped by FOMO, the fear of missing out on all those goodies. For starters, buying an EV gave you huge breaks on a vast array of auto taxes, from the import tax, to the VAT, to the annual road tax. Toll roads and ferries were free for EV drivers. Heck, municipal PARKING was free (until 2017). If that doesn't give a driver FOMO I don't know what will. 

You can gape at the full list of incentives below, I've reproduced it here from the Norway EV Association's website (which is in English, helpfully, and maybe also to give the rest of us outside Norway an acute case of FOMO).

No wonder that by 2021, 86% of cars sold in Norway were electric. 

You would think that Norwegians would now sit back, shout "Ska!", and down a glass of aquavit, for having arrived at the electric future. But no. Not content with having one-upped the entire world in EV penetration, Norway is now taking the next step. Seems their new motto is, 

We don't need newer cars,
We need fewer cars.

The Norwegian transportation minister has said Norway will focus on making it more attractive to walk, bike, and take public transit.

They didn't start this recently, this shift has been in the works for quite some time. If you look over the list of incentives, you will notice that a number of them are being phased out. For instance, toll roads were free to EV drivers until 2017, but starting in 2018 they paid half the toll, and starting 2023 it's 70% of the toll. This makes sense: once everyone starts to buy an EV, the FOMO ploy doesn't work so well any more. Also it gets expensive.

So starting next year, Norway is going to re-introduce the VAT, and in a progressive way, that is, the more expensive the car, the higher the VAT rate. This will have the effect of discouraging the sales of all EVs, but especially that of larger, more expensive EVs. Having fewer large and heavy vehicles will make streets safer for pedestrians and bicycle riders, in line with the country's Vision Zero policy.

In the capital, Oslo, the Vision Zero policy has resulted in zero traffic deaths in 2020. They achieved this stunning success by building out safe pedestrian and bicycle infrastructure, but especially by reducing the number of cars on the streets. Noway wants zero traffic deaths in the whole country, and reducing the number of cars everywhere will go a long way to achieving that, because car drivers are the cause of the majority of traffic deaths.

This graphic shows who dies in traffic on European roads in 2019, and who caused those traffic deaths. Data from the European Commission.

CelloDad says the Norwegian government is manipulative. Of course they are. But corporations also manipulate you, through their ads, only they do it mostly for the purpose of selling their stuff to you. If Norway's government uses incentives to nudge Norwegians into doing the thing that is right for their health, for the planet, for the health of their communities, then more power to them. Note that they didn't ban the sale of gas or diesel cars (they will do that in 2025); they merely made EVs irresistible. 

Let's see how long the rest of us take to catch up with them.