A bunch of the questions I saw asked about hydrogen on the UK rail network was the comparatively large size of the hydrogen tanks needed, and whether packaging of tanks of sufficient size was going to practical.
The hydrogen source might change pretty soon, so. There are a ton of initiatives right now aiming at green hydrogen, all over Europe, Northern Africa and the Middle East.
Not really. Who will invest in a facility, that runs occasionally on excess wind energy and stands rest of the time still?.. I want my investment working 24/7 with max 5 minutes maintenance each week.
How often is there excess power? To be economic there will likely be purpose built to run on wind whenever the wind blows, not just when the wind blows AND there is excess power. The capital cost of electrolyzers is substantial and will need to run a lot to pencil out.
It happens quite a lot, actually. Search the net for negative power prices and you'll understand the mechanics (for example, [1]).
So if a supplier can use that excess power to generate another product which can be sold, that's a win-win for them: they won't have to pay the penalty for oversupplying the grid, and they can sell the generated hydrogen for additional profit.
"The number of hours with negative power prices in Germany increased by around 50 percent to 146 hours in 2017, which translates into 1.6 percent of total time"
So if you're only going to run it when power costs are negative, you're amortizing the capital costs over running the plant for the equivalent of six days a year in 2017 Germany.
This is changing rapidly in many countries. House and large farm PV is getting super popular, more wind generators are being built, etc. Wind grows 10+% every year in Germany and solar ~5%.
I agree it's going to change. Overprovisioning of renewables is going to be necessary if we're going to rely on them alone, and long term I am excited about hydrogen.
But parent's link didn't really back up their claims, and concerns about capital efficiency for infrequently used plants are valid.
Solar being preferred energy source from what I heard. All you need after that is some access to ports and the hydrogen can be shipped wherever you want. Nice idea actually.
I will bite. This doesn't rule out why it cannot work out.
There are some strong assumptions behind this article, it chooses the following scenario: Wind + Solar + H2 for seasonal storage. And then proceeds to dismantle it. But nobody said this has to be the scenario.
I think it's far more likely something like:
Wind + Solar + hopefully clean base load (e.g. Nuclear) + Hydro + Hydro storage + Lithium storage + H2 storage for transport (planes, trains, ships) + H2 storage for seasonal purposes
Fact of the matter is, there is no clean alternative to H2 (at the moment) for large transport vehicles (i.e. cargo shipping, planes, trucks) so unless you are willing to keep using carbon based fuels for these purposes you are stuck with H2.
Biodiesel is a nearly drop-in replacement for No. 2 diesel. It's not carbon-free in current form, but neither is hydrogen, and there are viable carbon-neutral biofuel cycles, albeit ones that are substantially more land-intensive than modal contemporary practices.
That's all great, except that it simply doesn't exist at the moment. Nearly all of our hydrogen comes out of oil refineries as a byproduct. If you're going to use electricity to make hydrogen you might as well use it to make synthetic fuel and skip the whole hydrogen nonsense.
Even if everyone bought electric cars tomorrow refineries would still be there operating at about 50% of capacity. Isn't it better to capture waste hydrogen?
Isn't this the exact same argument people made against electric vehicles - for the majority of Tesla's existence the reality of owning an electric vehicle has meant burning fossil fuels to generate electricity to charge the car.
The point of running off hydrogen or electric is so that you can figure out the problem of generating the source at scale.
What straightforward process do we have for making synthetic fuels with electricity?
My understanding is that synthetic fuels tend to be some form of hydrocarbon, which means they need a source of carbon. Either you make the synthetic fuel at the exhaust stack of a fossil fuel plant (so you still have to burn fossil fuels) or you spend huge amounts of energy collecting CO2 from the air (is that even a proven process yet?)
Hydrogen has a straightforward and well understood process to make it from water. What's the hydrocarbon equivalent?
Apparantly, the biggest users of hydrogen is, among others, the chemical industry. It could also be a potential solution to power stuff like container ships. But we'll see what comes out of all these initiatives.
A bunch of the questions I saw asked about hydrogen on the UK rail network was the comparatively large size of the hydrogen tanks needed, and whether packaging of tanks of sufficient size was going to practical.