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Comment by GiorgioG | Hacker News Reader

I don't understand how the math adds up. If we all move to EVs, the demand for electricity will go up (a lot!) But I don't see how we're planning to meet such demand with our current power grid. Which of course in turn means that your electric bill will be in for a shock. Furthermore how will this work for emergency situations when power is out for days (think emergency services, police, etc.)? How about the military? How about portability? Being able to store fuel in 5 gallon increments in a cheap container has no equivalent in the EV world.

Maybe I'm just getting older and 100 years ago I'd have said "Well, I don't have to fill up my horse with gasoline to get him going..."

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If we all buy EVs we'll build a better grid.

Just like how we built gas stations when we all bought cars.

EV adoption is a curve just like anything. There isn't going to be a switch where yesterday there were few EVs and today everyone had them. Its a function that can be predicted and prepared for.

Also you can carry small batteries or generators. It won't be as portable as a 5 gallon can of gas. But so what, not everything will have a 1 to 1 analogy with gas cars. But small problems like that will be solved or worked around, people are smart and are always looking for new products to develop and sell.

This. I will take more than a decade of majority-sales being EV to convert the fleet. That's MORE than enough time to steadily upgrade the grid.

> But I don't see how we're planning to meet such demand with our current power grid. Which of course in turn means that your electric bill will be in for a shock.

We are definitely going to use more electricity — that's why everyone has been planning for major upgrades — but that's part of why solar is so useful since a lot of the existing grid demand is used at times when solar is generating peak capacity (i.e. summer air conditioning), and we've seen a lot of efficiency improvements which are reclaiming some existing capacity (e.g. at the turn of the century, a desktop computer used 1kw, your lighting was 10x more wattage, your AC, fridge, etc. were far less efficient, etc.) — that doesn't solve the problem but it takes some of the sting out of it.

In the case of an EV, my house is entirely electric including a heat pump + resistive heating. Charging a Tesla Model 3 completely is somewhere around one day's usage in the winter (~20℉ outside) and since that's a 200-350 miles range you're unlikely to be doing that every day or every other day. Most importantly, that seems well within the power output a solar array can provide — since cars are idle something like 95% of the time, you have plenty of opportunity to charge them off peak or when renewables like solar or wind are producing well.

That to me doesn't seem like an intractable problem but rather something which can be done incrementally along with other desirable work such as upgrading the grid to be more resistant to things like storm conditions.

> a desktop computer used 1kw

Desktop computers didn't use 1kW on average back in 2000. That would have been an insanely high-end machine and nothing like the average home PC. A lot of components were passively air-cooled or had a tiny heatsink with a small fan, you're not running 1,000W on something that may or may not even have a fan. Most computers I had back then had 200-300W power supplies. Add another 100W for a CRT monitor and that means each desktop really used something closer to 400W max. Usually you don't run at the max rating of your PSU, so really something less than that.

EDIT: The TDP of a Pentium III (released 1999) was 30W. Add another 20W for a hard drive, another 10W for an optical drive, and 100W for the motherboard and RAM, and that's ~160W for a basic home computer in 1999. AGP allowed for ~50W of power, extra power connectors on GPUs back then was pretty much unheard of so even with a fancy GPU you're only looking at ~210W of power for a decent 2000s era PC.

There were plenty of 400-500W power supplies in use back then, and 100W was on the low side for a non-tiny CRT. Don't forget that people commonly had multiple hard drives and/or external drives because storage hadn't saturated for the average user yet (oh, so many people learned the hard way that Iomega was not the answer…), and things like personal printers were more common since home networks weren't. I'm probably biased a bit as the home users I knew were mostly professionals rather than hobbyist but when people were speccing out UPSs they tended to assume numbers which these days we'd only see for beefy servers.

The bigger challenge is that while EnergyStar made a big improvement, it took a number of years to become something you could assume. Problems with firmware and software support meant that a lot of people disabled it to avoid problems and systems didn't spend as much time in lower-power states.

Restoring power to emergency services (or even ensuring they don't lose power in the first place at some expense) is already a thing. Your hospital is in pretty rough shape without electricity today and likely has stand-by generators. Those could run on Green Hydrogen in some Zero Emissions future.

However in respect specifically of electric vehicles, remember ICE vehicles are not efficient. The motor in your petrol or diesel car is optimised for size, weight and acceleration, not for energy efficiency, because nobody would buy a car that's the size of a house, or weighs twenty-five tonnes, or takes an hour to get to walking pace from a standstill. You may have noticed from household appliances that electric motors are small, light and have great acceleration, but it's less obvious they're also very efficient. So this means an EV only needs maybe 60% of the energy you needed for a petrol or diesel vehicle, reducing the demand on electricity compared to what you might expect.

We might well end up with more load management to reduce the "duck curve" but there is a lot of unused capacity at off-peak times, charging your EV at 1800 when you're also cooking food, cooling or heating your home and so on may not make sense, the pricing incentives can strongly encourage you to tell it to wait until say 2300 when you're in bed and the grid load is lower to fill itself back up for tomorrow.

> Furthermore how will this work for emergency situations when power is out for days

As someone who has been through multiple emergency situations where power has been out for days, a gasoline engine doesn't help the average person a ton past their current tank of gas in their car. Most people don't have gas generators, they don't have a 50gal drum of petrol in their garage, and if there was a disaster big enough to wipe out power for your home for days chances are a lot of gas stations are either without power or often without much gas to sell you.

Meanwhile, if you had a decent solar install and if whatever calamity took out power for days didn't also destroy your panels, you could potentially recharge your car if its still sunny out. EV + solar could mean you can be self-reliant on your transportation energy instead of relying on trucks making it into town, delivering it to the few distribution points still operational, and hoping you were one of the ones that made it after waiting in hours long lines. Obviously several big if's on that one.

While there is definitely a push for more EVs to be sold, I can't imagine there's really that many people pushing for truly 100% EV only on the road anytime soon. Even if 90%+ of passenger cars are EVs there will still be a place for petrol/diesel. I'm overall pretty skeptical on battery-powered long haul trucks largely due to trade offs of energy storage mass vs payload mass when thinking max weight ratings reducing the effective amount of payload per trip. Emergency services vehicles are expected to be pretty self-sufficient and carry massive amounts of energy with them for potentially long periods of time, diesel and petrol is way more energy dense even if you're only getting 30-40% efficiency in getting the energy out of it. So this "all move to EVs" is really more like all the sedans and crossovers, a decent chunk of medium-sized vans/intra-city trucks, and maybe the daily police patrol cars not necessarily all the heavy trucks used by emergency services.

Who knows though, maybe we'll see some bigger breakthroughs and quick field-deployable solar + battery or nuclear emergency service base stations will become a thing in the future which could mean after an initial truck delivery that field station becomes power self-sufficient which would be nice as that's one less thing to worry about logistics-wise. Otherwise you end up needing the constant supply of fuel to keep those emergency services operational after a disaster which can be challenging.

> If we all move to EVs, the demand for electricity will go up (a lot!) But I don't see how we're planning to meet such demand with our current power grid.

I don't think anyone has proposed more EVs without an improved grid. In fact, this January, the DOE announced a "New Initiative From President Biden’s Bipartisan Infrastructure Law To Modernize National Grid" [1]

> Being able to store fuel in 5 gallon increments in a cheap container has no equivalent in the EV world.

Batteries? I have multiple for my son's Peg Perego John Deere 12v [2]. My vacuum also has multiple batteries that I swap.

[1] https://www.energy.gov/articles/doe-launches-new-initiative-...

[2] https://www.walmart.com/ip/Peg-Perego-John-Deere-Gator-XUV-1...

A gallon of gas weighs 6.1 pounds. 5 Gallons + a container is ~35lb - highly portable. That gives me roughly 100 miles of range for my vehicle at a total cost of around $20 (plus the cost of the container, said another $20.)

A 50kW Tesla (model 3) battery is what, roughly 700lb and provides a range of ~220m miles if I'm not mistaken? Batteries of this size are simply not portable, nor are they cost effective to keep 8 in case of emergency. I live in an area that has occasional hurricanes and when one is threatening the area I go fill up 8 5 gallon gas containers and store them in the yard. Assuming the storm passes without major damage (power outages, etc.) we'll use that fuel to fill our vehicles' gas tanks. There is no equivalent of this in this new-fangled electric world. Until batteries become smaller, light and a hell of a lot cheaper, I'll be sitting on the sidelines.

Gas is very energy dense and gas engines/generators are very cheap, but in an emergency I would rather have batteries.

A large portion of cars are low on gas at any one time because it is customary to run your tank to near empty. During an emergency gas can be hard to get. Electric cars are almost always above 50% charge. Gas generators need maintenance and fuel just sitting there need stabilizers. During hurricanes and freezes a lot people can't even get their generators working and good portion of those that do, don't use them safely. A battery backup is expensive and won't power things as long but it is dead simple to maintain and use. If you have fixed or portable solar panels to pair with your battery it can keep the most important appliances and electronics in your house going for a while.

> There is no equivalent of this in this new-fangled electric world. Until batteries become smaller, light and a hell of a lot cheaper, I'll be sitting on the sidelines.

The entire premise of the discussion is a world where we have transitioned the economy completely to EVs. I think it's safe to assume that, in this new energy world, batteries would be smaller, lighter, and cheaper. This has been the observed trend since 1991 [1].

[1] https://ourworldindata.org/battery-price-decline

Home solar. Reduces a huge (or all) of the grid need. It can be more organically rolled out than the cheaper but longer lead time of utility server.

Especially if the EV's massive battery can serve double duty as a "powerwall" type buffer as well. And if you have a two-car family, you'll have two buffers.

The military will use ICE/fuel if they need to. Or hydrogen + fuel cell would apply to them? Or methane + fuel cell? They'll do what they have to do, and there will be oil oversupply at that point.

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