This is based on a talk given last night by Nicky Ison of the WWF on hydrogen power.
The advantage of hydrogen as a fuel is fairly simple. You burn it and that produces energy and water. No greenhouse gases. It is reasonably energy intense, perhaps not as good as coal or oil, but it is more likely to be useful for processes which require large amounts of power, than renewables and storage can be. These include steel production and powering huge mining trucks and shipping, or other trucks which have to travel long distances quickly.
Hydrogen is unlikely to be used to power ordinary cars. There is already an electricity infrastructure, and we would have build a new, and country wide, hydrogen infrastructure to make it useful to for ordinary people. Its more energy efficient to use electricity, than to make hydrogen. and transport it. However, in big vehicles the weight of batteries becomes significant. Hence the possibilities of use.
Having said its a great form of energy, it is good because it is extremely flammable and hence dangerous. It does burn so fiercely that materials nearby may not be hurt, as the flames rise upwards. Hydrogen is often transformed into ammonia to help safe storage and transport, and ammonia is not that great for human health. Hydrogen stays as a gas until very low temperatures are reached (−252.87 Celsius), so freezing it or liquidifying it is not practical.
There are three ways of producing Hydrogen. In the first two, coal or gas are used as raw materials (processing them in different ways). These methods could be powered by renewables, but are perhaps more likely to be powered by coal or gas. The third method is to extract the hydrogen from water by electrolysis – that is passing an electrical current through nearly pure water. This third method can use renewable energy, and produces more-or-less no harmful waste products. The other two methods naturally produce greenhouse gases.
There is an argument that the greenhouse gasses from fossil fuel hydrogen could be stored underground through carbon capture and storage (CCS). This is almost certainly a fantasy. CCS does not work well enough, and costs a lot. It is not happening for most coal and gas energy production now, and even in working projects little carbon is being stored, so there is no reason to think it will happen for hydrogen production in the near future.
Hydrogen production is already a major industry, it is used to produce ammonia and methanol, and that goes into cleaning products, fertilisers and explosives. It is highly polluting. 99% of global hydrogen is made from coal and gas and produces approximately 1% of global greenhouse gas emissions – that is more emissions than attributed to Germany or South Korea. Hydrogen production accounts for about 6% of global methane use.
Big renewable Hydrogen/Ammonia plants are being built in China, Saudi Arabia, Spain and Germany. So the idea is taking off, and some people, at least, do not think it impractical in their local conditions.
Conditions of Use
The WWF argues that if we are going to use hydrogen it must be:
- Renewable hydrogen, not hydrogen made from, or powered by, coal or gas.
- Traceable. So we don’t get established fossil fuel hydrogen being substituted onto the market for renewable.
- Deploy stringent safety regulations. If we transport it as ammonia, then we have to also consider the safety issues of that.
- Minimising environmental impact, and maximising environmental co-benefits [This is a bit vague]
- Part of the electrification of energy use and production. This is not an excuse for gas or coal to come back.
- Cheap for Australian customers. We don’t want a replication of the gas (methane) situation in which it is cheaper to import methane than it is to buy local methane.
Renewable hydrogen could conceivably be exported to Singapore, or Japan. But that needs us to build it up quickly, before other people lock in contracts.
We might also use it to start up “green steel” production, and “Green aluminium”. We could also start putting hydrogen into gas pipelines, if we reduced the amount of methane we consumed.
1) The classic problem is that Australian business is not geared towards making things and exporting them. Our business likes digging things up, growing things, or selling real estate. That is about it. The only person person interested in Green Steel in Australia, who is widely known, is Sanjeev Gupta who is an Indian born Briton.
I’m told that compared to other countries there is a dearth of Australian industrial policy that is helpful to people starting up. It is possible that this could get in the way, or that the Government’s declared preference for fossil fuel Hydrogen, could also inhibit renewable hydrogen.
2) hydrogen production is not very energy efficient. It takes lots of energy to make, compared to the amount of energy released by burning. Energy Return on Energy Input (EREI) is not great. This means we can only do green hydrogen, when we have masses of excess energy being produced. Renewable farms could conceivably produce hydrogen when they can’t sell electricity, because they are producing too much. However, this assumes that we can build that many large scale renewable options, and still have them make a profit, and that we can add the cost of transporting Hydrogen to this, without making it difficult.
3) You need clean water to make renewable hydrogen. I think the WWF tend to bypass this problem too quickly, but I don’t know how much water is needed – I would have thought quite a lot, but I could be wrong. Australia is not renown for its fresh water supplies. Sea water is probably no good. To use sea water we would have to have large desalination plants. That would take even more energy. Bore water usually contains impurities, and that might have to be purified as well. It was suggested we use water in tailings dams. But that is also impure, and probably not enough in any particular pool for us to set up an industrial plant, so the plant would have to be moveable, which could be quite difficult.
So the priority would be cheap water cleaners which can operate at large volumes. This is something the world will need soon anyway, so working on this would be useful. However, because something would be useful, does not mean it can be done in the current situation.
The other possible light here, is that if we stopped coal mining, we would have heaps more water.
According to the National Hydrogen Strategy, producing “enough hydrogen to satisfy Japan’s projected annual imports in 2030 would require less than 1% of the water now used by Australia’s mining industry each year”.Energising the Economy with Renewable Hydrogen, WWF Australia, P 14.
If we are going to try hydrogen, and we won’t know whether it is doable unless we try, then we need to add at least two points to the WWF list of conditions
- A coordinated industrial policy that aims to get renewable hydrogen off the ground, encourages industry to use it (such as green steel for export), and either spends the money that is currently marked for taxpayer funding of gas (methane) pipelines on hydrogen pipelines, or gradually converts the current gas infrastructure into hydrogen infrastructure.
- Make sure that any water which is consumed by hydrogen manufacture does not take away from farming, environmental or human drinking supplies. This could be done by tightening water regulation for coal mines and slowly decreasing the amount of water that coal mines can take, deliberately or ‘accidentally’.
Without these extra points, hydrogen will almost certainly fail to help the situation.