Comment by bkor | Hacker News Reader

Comment by bkor | Hacker News Reader

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Efficiency has a huge impact on the cost/economics, something that you've highlighted. If significant more energy is needed, it'll likely be more expensive. Hydrogen is sometimes only a third as efficient as other solutions. It's pretty logical to assume it'll be

> In the early 1900s, gas was less efficient than electricity too

I think you mean gasoline instead of just gas. Hydrogen requires huge amounts of energy before it's easy to transport, which is what you responded to. In any case, in the early 1900s, gasoline had a huge amount of stored energy. It was a matter of using it efficiently, you're comparing apples to oranges. With Green Hydrogren too often people say that some technological improvement will solve the drawbacks. While ignoring that for e.g. hydrogen it's not so easy, for other options it is/was.

Same for the often suggested "solution" of using surplus energy. A factory that doesn't work 24/7 is more costly. Aside from that I understood that hydrogen is best produced continuously for it to be efficient.

> Efficiency has a huge impact on the cost/economics

It doesn't have nearly as much impact as other factors, such as abundance of the material, how easy/practical it is to work with it (which influences both demand and supply), whether mass infrastructure for it already exists (although this is more relevant in the short-term rather than long-term), etc.

These factors impact the economics of an energy source much more than efficiency, and economics is by far the most important factor in deciding whether an energy source will be used or not (and how much of it), not efficiency.

e.g. if hydrogen is only 10% efficient but there's 10 times more of it on Earth compared to a similar energy source that is 90% efficient, then hydrogen wins (all other factors being equal).

As another example, if hydrogen tanks in cars explode 100 times as often as gas tanks, then it would probably be a complete non-starter for powering vehicles, regardless of efficiency.

But the efficiency of something goes directly into the economics.

If you need need to build out a grid to power your cars, you'll 3x as much energy at the source to get the same amount of energy into the tyres.

Which might mean very little compared to the other factors.

3 x 10 cents, which could represent a fixed amount of an abundant and easy-to-work-with energy source (therefore cheap) which has 33% efficiency (hence the 3x cost factor), still costs much less than say, 1 x 5 dollars, which might represent the same amount of energy provided by a scarce and/or hard-to-work-with energy source (therefore expensive), even if this energy source is 99.999% efficient (hence the 1x factor).

As an analogy, let's say you live in a community on an isolated island and you need to eat.

You can satisfy your hunger / nutrient / energy requirements with 1 coconut or with 5 apples (which means we're assuming one apple is only 1/5th as nutritious/efficient as one coconut in this example).

Which fruit serving will be cheaper? You can argue "if you eat apples you will need 5x more of them, therefore they will be more expensive!".

But of course, that might not matter one bit.

The problem is that maybe on the island there might only be 10 (reachable) coconuts but there might be 10,000 reachable apples, so the 5 apples would be much, much cheaper than 1 coconut.

Or perhaps there are also 10,000 coconuts but there are no knives on this island so they would be very hard to open and eat. Therefore you wouldn't be able to find coconuts at the market because nobody would want to pick them and sell them, since nobody would want to buy them despite everybody wanting to eat fruit every day.

>Efficiency has a huge impact on the cost/economics

Not in the way that you think, no. For all intents and purposes, we have limitless energy. The problem was never that we don't have enough capacity, because we can scale capacity as much as we want. The only thing that is required is that energy generation (i.e. $/kWh) is cheap enough, and this seems feasible with solar and wind and maybe fission and later one fusion or other sources.

>you're comparing apples to oranges

You are the one saying, "just attach a transmission line to it" or "just put a battery in it", without thinking of all the cases where this is just not possible.

Nobody is arguing that you should start powering your toaster with hydrogen. You all are attacking a strawman, it seems.

You would have to solve the problem of getting soggy toast from the exhaust steam.

Unscheduled detonations would put an, er, damper on adoption.

I believe that would be toast toast.

Efficiency is important for cost/economics but so is the abundance/scarcity. Fossil fuels are a non-renewable resource and are in theory supposed to get more scarce in the future driving up costs/economics while hydrogen is the most abundant element. Granted it is more cumbersome to capture, transport, store, and distribute it now, I don't think it's a outlandish theory that at some point in the future, technological improvement in hydrogen industry combined with more scarcity of oil could change the calculus on the cost/economics of oil vs hydrogen.

When solar-powered hydrogen production cost gets cheaper than new petroleum extraction, exploration and field development will wholly collapse. The cheapest, seemingly inexhaustible existing fields in Arabia will satisfy remaining demand.

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