2G Energy – Hydrogen CHP Webinar – Q&A Summary 

 2G Energy - Hydrogen CHP - Webinar Q&A

Following 2G Energy’s Hydrogen CHP webinar, we have summarised the Q&A for quick reference.

If you missed the webinar, follow the link below to catch-up with everything that was discussed:

Hydrogen CHP – CIBSE Certification – Webinar

If you have any other questions that you would like to ask, please feel free to get in touch and we will do our best to answer them for you or you can email Martin Kenzie directly at: m.kenzie@2-g.com

Q & A

Question One

Could you use this equipment for a portable generator setup or does the infrastructure to supply the fuel limit that as an application?


Martin Kenzie: Strangely, no because we’re having an awful lot of conversations at the moment about temporary power, I mean generally I mean a lot of the times 90% of the application the CHP is obviously integrated into a building. But we’re actually we’re having an awful lot of conversations at the moment about supplying the CHP containers that can be used in temporary power situations whether it’s building sites or whether it’s music venues and once again there’s a lot of work being done in some of the scandinavian countries about producing obviously containerized hydrogen deliveries.

So once again we can deliver an engine to size, whether we’re doing it or whether a temporary company are doing this, and then effectively you have two containers, you have the container with the engine inside this and you have a container obviously with the hydrogen storage in this and then once again it’s just connecting on to it in exactly the same way you could use a diesel generator except it’s a natural gas generator.

Depending on the applications, a lot of the science you wouldn’t even envisage running it as a CHP. We envisage just running, it’s a straightforward gas engine, a gas generator, we wouldn’t even put the heat recovery heat exchangers on it. So yes it’s very viable and there’s a lot of conversations we’re having about that specific thing specifically around building sites, obviously because people don’t want diesels generators if they’re building obviously low cost housing or low carbon housing and also things like music venues etc. So, yeah, it’s definitely happening and those conversations are happening already.

Question Two

To an extent, does that help request the technology ahead of piped hydrogen supply?


Martin Kenzie: Once again, I said that the applications that we’ve been looking at for this specifically are about so that they wouldn’t need temporary installations.

They wouldn’t need effectively piping up because obviously there’s no hydrogen infrastructure at the moment anyway so it would be a case of this and you end up with an engine being delivered and you have a hydrogen containerized storage solution being delivered and obviously that the container with obviously the hydrogen stored have all the gas in it to drive the engine. And then it’s just case of how large or how much density of hydrogen you need inside that container or that storage vessel. And how long do you want to run the generators for. But, yeah, be any sort of like piping up into a gas infrastructure or anything else it’s effectively like you have a diesel generator and you have a diesel fuel tank sat next to it. You would have a hydrogen engine and you would have a hydrogen fuel tank sat next to it, it’s exactly the same thing.

Andrew Geens: I wondered whether off-grid applications that use LPG were sort of close parallel to this as well?

Martin Kenzie: Absolutely. I mean we run an engine sometimes on LPG anyway and, once again, I said it’s all dependent obviously on the size of the engine and obviously the size of the storage vessel because obviously I mean if you wanted say a megawatt engine, you might be changing that container every two days to get it filled.

Once again, you then start thinking about whether you would actually use something like liquefied hydrogen and then obviously having an evaporator to convert it back to a gas to run into an engine. Once again, there’s an awful lot of conversations that are going on about that about what storage medium is needed depending on obviously the quantity of gas and the release rate that’s needed.

A lot of the times I said we’re specifically talking about gases but we also know in the larger applications we’re also talking to a lot of people who were thinking about producing liquefied hydrogen.

Question Three

The units “pKwg” on the hydrogen cost graph on page 18, what is that unit?


Martin Kenzier: pence per kilowatt of gas.

Yeah, I mean, as I did these slides about probably three years ago now. So when we were starting to think about this and obviously started to think about obviously where the sort of the financials or the economics of this sat, so we’ve done some calculations based on obviously where it was at the moment and what we need to get a breakeven position.

That’s why it says 19.49 at the bottom. So effectively we didn’t know three years ago if BEIS was thinking about doing it on ROCs or something like that equivalent. So we knew generally we could get hydrogen for about 12.5p per kilowatt so we thought right if we’re trying to get to a breakeven point of 15 or 20 years we’re going to need ROCs subsidies about 19p, which once again that’s nearly triple or four times what ROCs payments normally are. And then we thought okay, but what different prices of hydrogen do we need to be to be that breakeven, what sort of subsidy is needed to hit that breakeven position and that’s why we got down to the stage where we needed about 5-5½ pence of hydrogen to be in a breakeven position of 15-20 years.

It’s still not an economic position but it’s that breakeven position where you might be then saving several thousand tons of carbon, even though it’s not an economic payback or it’s a net present value zero position so it was just a lot of different calculations we ran about where we think the price of hydrogen has to be before you don’t need any subsidies. And, I said, it isn’t even the case where you have to get the hydrogen down to like a 1½p/2p where natural gas is to make it work or to make it sort of breakeven. You just generally have to be around that 5p-5½ p without any subsidy at all to make it economic and we see that coming up as electrolyzers start getting bills and obviously the cost of those starts coming down and because obviously one of the big costs of generating hydrogen which is obviously part of the electrolyzer is actually the cost of electricity.

But, there’s some of the novel contracts now where people are looking at because if people have ROC contracts on their wind farms, they want those wind farms spinning especially at night. They don’t want then staying out of wind so some of those are able to offer effectively zero cost electricity contracts at night so then all of a sudden you’ve got zero cost electricity going into an electrolyzer producing hydrogen because the wind farm company was getting their subsidies by the ROC payments. So, once that changes the economics as well about how people are actually looking about the model of this about where the cost of hydrogen production is going to be.

Question Four

Are you able to quote a rough figure? What is the cost per kilowatt hour for the additional injectors to convert to hydrogen?


Martin Kenzie: It’s about 15% of the engine for us to convert an engine to 100% hydrogen’s. Roughly 15%.

Question Five

Is there a safety concern because hydrogen is colourless?


Martin Mckenzie: Not really. Once again, I said, I mean millions of tons of hydrogen are being used all over the world already anyway in industry and everything else but no we haven’t really had any concerns about the colour of it or the lack of colour in it.

Andrew Geens: Yeah, perhaps in a boiler rather than an engine flame colour which is useful for a gas engineer might not be the same with hydrogen.

Question Six

Someone’s heard about a trial for a hydrogen grid pipeline in the north of England. Is that something you’re aware of?


Martin Kenzie: Well there’s lots of projects going on. I mean, there’s the h-100 in Leeds, there’s all the projects up in Dundee. I mean, Dundee’s fighting for itself, probably the first hydrogen city in the UK. There’s the Acorn project, they’ve got some. Grange Mouth. I mean that one project that’s a big electrolyze connected to the of the the Scots wind farms and if that comes online in three years time they reckon that could that can put 6% or 7% hydrogen into the entire gas grid just on one project but that’s why in places like Dundee and stuff they’re also looking at putting in 100% dedicated hydrogen pipelines and that they put up with calls for industry on who might want to connect to that pipeline.

I mean, in Germany, where our manufacturing site is in the next 12-18 months, we’ve got a 100% dedicated hydrogen pipeline going around the back of our factory.

Question Seven

I think you may have answered this but someone’s asked with a specific number so I’ll just put that number into the mix. It’s about viability at a smaller scale, less than 500 kilowatts?


Martin Kenzie: Well, once again, the smaller engines we’ve got I mean the one in Orkney’s only 115 kilowatt engine. It’s like everything else, generally the scale of the economics gets better and better and better as it gets bigger and bigger and bigger, but once again at the moment electrolysis isn’t a certain isn’t that sort of issue, it’s the actualizer probably might cost more than the engine itself. But, once again the economics don’t work at all in any sort of scale so that’s why most of the projects we’ve done people are thinking “well, if it’s not going to work economically why go for a megawatt engine when that’s ten times more non-economic than 100 kilowatt engine”.

So, that’s where it is at the moment, that’s why a lot of these are effectively demonstrational trial projects to prove the infrastructure and everything else but obviously as the electrolyzer sort of like industry or the I mean everyone’s just waiting as effectively for BEIS to make the announcements on what the subsidies the hydrogen generation and then as soon as that happens, I mean most of the electrolyzer companies, I mean, they’re building like gigawatt factories to try to produce electrolyzers. They’re just waiting to see what’s happening because it’s like the thing at the moment you can produce the hydrogen at the moment but unless you’ve got a use for this what you’re going to do with it you can’t inject it into the gas grid at the moment in the same way you can biomethane but all of those safety legislations and everything else are all getting changed in the background so sometime later this year maybe next year you’ll be allowed to inject hydrogen into the gas grid. The same way you can biomethane and, once again that then kick-starts that economy. But it’s the wind, it’s the thing because we have too much wind. I mean, generally, throughout the whole of Europe about 30% of the wind farms have to turn out of the wind at night, so there’s so much wasted potential energy and you think well rather than waste it convert it to hydrogen, make hydrogen, that’s how most of the projects that we work on work as all the ones in Germany they’ve just produced hydrogen at night. They’ve got no other use of that electricity so rather than just having an idle wind farm not doing anything produce hydrogen.

Question Eight

With a naturally aspirated engine, can you run 100% hydrogen without modifications or changing the injection system?


Martin Kenzie Answer: Yes

Andew Geens: That’s a nice easy answer. It was only going to be yes or no.

Martin Kenzie: Yeah, it’s only on our turbocharged engines where we get the problem. I mean all ranges of engines generally aren’t turbocharged anyway. We were concentrating on our generator range of engines to start out with because of that charge we’ve got a higher power output of them because, generally speaking, normally when you run 100% hydrogen you’re getting about anything from a about 20% d-rating of the engine because one of the issues with hydrogen it’s got no knock resistance. So, you can’t run the engines at the moment obviously with the same power output as you start getting knocking on the engine.

The R&D departments are working on that because at the moment we’re injecting hydrogen, probably about 4 bar, into the cylinder heads. We reckon if we move up to maybe 20 bar we can alleviate the knock issue on the hydrogen and then we’re effectively going to be running the engines the same power output on hydrogen as natural gas.

Question Nine

When you switch over from natural gas to hydrogen, what effect does that have on the output from the engine?


Martin Kenzie: Well, normally, yes. I think if we’ve got the engine set up to be running 100% hydrogen then we switch obviously to natural gas. I mean, it’s what we call a blending line. It’s something that develops for the biogas industry where sometimes if the biogas digesters didn’t have enough biogas they obviously still wanted the heat to run the anaerobic digesters. So, we always developed this technology to run natural gas into biogas and for the blending to keep the engines running . If we’ve set the engine up to run 100% hydrogen we wouldn’t go higher than the power output of the hydrogen. So, once again, if we’ve got the hook like our one megawatt engine , if we’ve got the hydrogen injection system on it and it’s configured to run at 750 kilowatts that we’ve run on hydrogen, they’ll be running on hydrogen. If we go on to natural gas we’ll still run it at 750 kilowatts, we don’t bother putting the power output out otherwise it means we have to change the compression ratios and everything else in the engine.

Andrew Geens: Yeah, I guess that question was driven by what you said earlier about the difference in calorific value.

Martin Kenzie: Yeah, no well, as I said it, even though we get a de-rated running hydrogen specifically because we don’t want to get the knocking issues on the engine, because the engine sort of like shake itself to death, once we’ve de-rated the engine once we know we want to run that derated value on natural gas we just have the ejection of the natural gas going up to that same value. We don’t obviously overpower the engine again.

Question Ten

With regards to the Dubai project, what mix was considered and what was the life expectancy? What was the efficiency between natural gas and hydrogen?


Martin Kenzie: The Dubai project doesn’t have anything to do with natural gas, we don’t even have a gas mixer on it. It’s a 100% hydrogen dedicated engine.

The reason being is because it was part of the hydrogen expo they wanted to demonstrate that you could produce. Obviously, the middle east wants to get into the hydrogen economy because to use hydrogen obviously all you need is wind, sun and water. Well, they’ve got an awful lot of sun, they’ve got an awful lot of deserts and they can get water so they can see that they want to move their economy from a basically chemical or petrol industry into a hydrogen economy. So, it was really a demonstration project that you could produce hydrogen using your sunshine and water so that that’s why the hydrogen expo was there to demonstrate you can use hydrogen engines.

You can use it in fuel cells, the buses etc. That’s all it was so it was just a demonstration project. I mean, obviously, they weren’t policing too much about the economics office because they’re not exactly short of money but I said it was never intended to run anything but 100% hydrogen into that engine. The efficiencies are basically the same whether you’re running hydrogen or whether you’re in natural gas.

Question Eleven

Another question about the portable situation. I think someone’s asking about the cost-benefit analysis on using this to fuel emergency standby generators rather than 35 second gas oil. Would there be a size at which that would become an option?


Martin Kenzie: Well, once again, but this is something that’s at the NHS and a lot are looking at this at the moment.

Now, the the NHS is quite funny actually because up until 20 years ago, I’ve done this an awful long time, 20 years ago like CHPs were the greatest thing ever for doing the NHS carbon targets and so that’s why we saw massive CHPs into all the NHS and then obviously the last couple of years people have been arguing saying ‘oh yes you can’t use CHPs anymore because obviously the carbon position’ and so the environmental people were the biggest prohibitors for CHPs and hospitals until they worked out that they’ve got this 20-40% carbon zero target and they had no idea how to do it.

So we met an awful lot of them, we said well it’s dead simple all you’ve got to do is just run the engines to100% hydrogen, that’s 80-90% percent of your target done. It’s at the same point they went, can we get rid of our diesel generators and have the hydrogen storage and have basically two engines, one that’s doing the primary power at hospital and one is the standby set. So effectively yes.

Question Twelve

Does hydrogen accelerate valve wear?


Martin Kenzie: Well, yeah, not really. Everything that we put onto the engine because when we do what we need we change this and obviously cylinder liners and everything else. Everything that goes on to the engine for the hydrogen running is obviously hydrogen, all the metal and everything else is all it’s all specified for running on hydrogen.

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