Comment by csours | Hacker News Reader

Comment by csours | Hacker News Reader

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> "But skeptics may wonder why engineers are devoting so much effort to developing the mild hybrid systems that could be seen as stopgap measures on the path to a fully electric vehicle fleet."

Let's do some napkin math.

Assumptions:

1. Gasoline will never exceed $10/gallon. (assumes eventual plant/algae sourcing/some kind of magic). 1a. Vehicles achieve 50 mpg (2 gallons/ 100 miles) via tricks like 48-volt.

Thus future gasoline MHEV vehicles cost 20 cents/mile to power, so $20 per 100 miles

2. Batteries get stuck at about $100/kWh. (maybe lithium etc never scales) 2a. Consumers are satisfied with 60 kWh batteries.

Thus BEVs cost $6000 more than comparable MHEVs (napkin math)

4. Electricity costs $0.20/kWh (assume some surcharge for the charging station). 4a. Your BEV gets 34 kWh / 100 miles (99 MPGe)

Thus to power your BEV costs $6.8 / 100 miles.

5. The difference between 20 and 6.8 is 13.2 - so you are paying off your battery at $13.2 / 100 miles. 6000/13.2 is about 450

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Conclusion: It will take 45,000 miles to pay off your battery, assuming the competition is a 50 mpg vehicle and gasoline is $10/gallon.

Additionally, the initial cost for a BEV is $6000 higher, which is quite significant for entry-level buyers.

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With 33 mpg and $5/g you have $15/100 mile, thus a 80-90,000 mile payoff.

With 33 mpg and $3/g you have $9/100 mile, thus 270,000 mile payoff

With 33 mpg and $2/g you have $6/100 mile, and you will never pay off the battery investment.

With 20 mpg and $3/g you also have $15/100 mile = 90,000

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Home Solar: add $10,000 to your battery = $16,000

50 mpg and $10/g you have $20/100 mile = 80,000 mile payoff

33 mpg and $ 5/g you have $15/100 mile = 107,000 mile payoff

33 mpg and $ 3/g you have $ 9/100 mile = 179,000 mile payoff

33 mpg and $ 2/g you have $ 6/100 mile = 267,000 mile payoff

20 mpg and $ 3/g you have $15/100 mile = 80,000 mile payoff again

Replying to myself: One thing the above does not take into account is the feeling of a BEV, which internal combustion and weak hybrids simply cannot match. I deeply feel that luxury customers will demand strong electrified powertrains after experiencing them.

Strong hybrids could match the feeling of a BEV, at a similar per-unit cost.

One issue is engineering and certification costs - manufacturers can only do so much at once or else shareholders get anxious.

Also not included are warranty reserves (how much to set aside per vehicle for warranty costs). More complicated vehicles call for more reserves.

> One thing the above does not take into account is the feeling of a BEV, which internal combustion and weak hybrids simply cannot match.

I absolutely agree about most luxury customers. However, there are certainly those of us in the minority who favor a more mechanical experience when driving a car, and most electric cars seem to move even further away from this in pursuit of efficiency, etc. Consequently, I don't think this market will exist for much longer once driving becomes more commoditized.

I'm certainly on a tangent by now, but there an interesting piece by Malcolm Gladwell in Car and Driver about a possible result of the rise of autonomous cars on car culture today: www.caranddriver.com/features/when-autonomous-cars-rule-what-will-happen-to-car-culture-feature

The big error in your calculation is, that you calculate only the cost of the battery, but not the cost reduction of removing the most complex parts of a combustion engined car: the engine itself, the gearbox and the whole exhaust system including cleaning. If you calculate this in, you should come up with very different numbers - a lot of experts think, that electic cars might be even cheaper to buy in the early 20ies years.

You are correct, it is napkin math after all. Assuming similar sales between mild hybrids and BEVs, the eventual cost of a BEV is probably only $2,000 to 3,000 more in the short term... but consumers make decisions based on differences $500 or even less.

I could do some more napkin math with engineering costs, unit costs, Bills of Material and amortization schedules... but you can be assured that automakers have done more than napkin math, and they are pursuing (as an aggregate group) both technologies.

The business cases for each of MHEV and BEV make different assumptions. I think it's great that different methods are being pursued. Eventually some automakers look very silly, but you can't tell which ahead of time.

So far electric cars cost more than ICE including this cost reduction

That is correct. Most car manufacturers currently pay way more than $100 per kWh battery capacity. Also, the electrical vehicles are made in much smaller numbers than combustion engined ones, raising production costs considerably. But for a long-term calculation, you cannot ignore the cost savings of leaving off all the combustion-related technologies. And that there are significant cost savings should be obvious.

>Gasoline will never exceed $10/gallon.

The consequences and repercussions of global warming and climate change plus Nixon era doctrine of interventionalist policy in the interest of maintaining global US oil hegemony have easily put real barrel cost easily above this. Iraq didnt pay for itself twice, after all.

Why everyone talks about switching to electric cars while nobody ever mentions electric heating of buildings as environmentally friendly alternative? Because it isn’t? Why bother with electricity-saving lightbulbs while EV owners burn the current like there’s no tomorrow...

There's plenty, like a lot, of shale oil available at $80-100/bbl, which allows for significantly less than $10/g gas.

The only meaningful challenge to $10/g gas is policy (ie taxation).

Algae derived oil, if it could be made to work at scale, has none of those problems. It is a not unreasonable upper limit for a totally renewable source of petrochemical fuel.

In most of Europe, gasoline is already close to 10$/gallon (1.50€/l or more).

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