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Comment by arijun | Hacker News Reader

I thought fuel cells were an energy storage system, not an energy generation system. Surely it’s cheaper to just connect the data center to the generation directly (either by upgrading the grid to handle it or building generators nearby).

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Fuel cells are an electricity generation method. They oxidize fuels (methane, hydrogen) at low temperature, electrochemically, without combustion—going directly from fuel to electrons.

This would have been simply a natural gas power plant, of a different type.

I'm really wondering about the air filtering needed for this to work. Gas turbines are already quite sensitive to bigger particles in the air but for the fuel cell membranes, this could be a much harder problem.

I bet you could spin the natural gas in a centrifuge to eliminate larger particles.

I would guess the natural gas is quite purified by that point, but for the fuel cell to work you need to combine it with air (or to be precise, the oxygen in the air) and a lot of it. So for the fuel cell membranes not to clog with dust and gunk they will have to clean in in some way to prevent issues, ideally without to much extra-energy use or expense per unit of air filtered.

How about a HEPA or ULPA filter? These are very mature technology, work extremely well, and are not particularly expensive.

Sure, that would work - but with the massive ammounts of air needed I would assume those would be quickly clogged and unusable.

Most fuel cells can't be recharged. They take combustible gases, re-assemble the molecules in the gas into H2O or something chemically stable, and release the energy delta as voltage potentials. The cells work purely as catalysts. Only the fuels are expended.

It's just a type of battery, that takes fuel, as its refillable energy source. Weird but it works.

Yes, there is a completely different thing with the same name. Race cars can use fuel cells to prevent sloshing. Those are basically fuel tanks with foam in them.

That was not my understanding. Unless this installation was supposed to be producing fuel on site somehow, fuel cells are a mechanism for turning fuel into electricity.

https://www.bloomenergy.com/technology/

In Motorsport a gas tank is called a fuel cell. That may be where the confusion lies

The literally dirty secret is that a Bloom fuel cell is a device for turning methane into hydrogen on demand to fuel a hydrogen fuel cell. It's still emits CO2 and oxides of nitrogen like a gas turbine. They should be a lot quieter though.

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