Written By:
John Jackson
Industry Editor
When it comes to decarbonisation in the built environment, not only is the scale of the challenge daunting, but so too are the decisions that need to be taken to ensure we achieve a truly sustainable way to heat and energise our lives. Today, although choices are available, the accepted way of heating a home and providing hot water is mainly through the use of a gas boiler. To meet our 2050 net zero carbon emissions target this has to come to an end, and work is underway, particularly around the retrofitting of the homes managed by Wales’ Housing Associations.
The approach being developed is one that involves making existing properties as energy efficient as possible and replacing gas boilers with air or ground source heat pumps, with the addition of PV panels to generate electricity from the sun that can then be stored in a battery. In addition “Smart” systems are deployed and technology learns how the household is using energy to help ensure the overall system is operating as efficiently as possible.
Of course this is a very different approach to the way we live in our homes today, and by contrast, at first glance, the potential for hydrogen boilers to be installed in homes as an alternative to gas boilers seems highly appealing. However, there are a number of reasons why it is unlikely to provide a simple “switch over” solution from gas to hydrogen for heating and hot water. To begin with, for hydrogen to be a green energy it has to be produced using renewable energy, and lots of it would be needed. The gas then has to enter into an infrastructure for distribution and it has the disadvantage of corroding metal pipes. That said, the gas industry has for decades been replacing metal pipes with polypropylene ones and it is estimated that by 2030 upwards of 90% of pipes will have been replaced. To make things a little more complex hydrogen storage and transportation also results in a loss of its energy. If liquidated it can be as much as 40%, although when compressed under high pressure the energy loss is lower at 13%.
H100 Fife is the world's first green hydrogen to homes heating network that will “heat around 300 local homes using clean gas produced by a dedicated electrolysis plant, powered by a nearby offshore wind turbine”. Due to go online in 2020, the location allows for green hydrogen to be produced and the experience of this project will no doubt be closely monitored to establish the viability of hydrogen in domestic homes. At the start of July two hydrogen homes were opened in Gateshead. The houses are intended to allow people the opportunity to interact with hydrogen appliances, including boilers and hobs, and different manufacturers will be using these houses as a showcase for their products.
Seeing hydrogen in action will help to increase understanding of how it can perform in a home, at the same time it's important to acknowledge that much of our housing stock is highly inefficient in terms of its energy usage. Even renewable energy needs to be treated as a scarce resource and for existing homes and new homes it is becoming increasingly important to ensure they are not just highly energy efficient, but that they will also be resilient to the impacts of climate change. In this respect, even in locations where it may be viable to use hydrogen to heat homes, those homes need to either be retrofitted to become energy efficient or in the case of new build they should be designed and constructed as energy efficient homes from the outset.
As every home will need to change the way it is heated, other options, including district heating schemes that could be hydrogen fuelled, will also be worth exploring. Whereas we are used to a simpler approach to heating our homes, in the future across Wales different solutions may well be more appropriate depending on specific location. The biggest challenge will be to ensure that by 2050 we have met our emissions target, and this does mean we have only a relatively short period of time to decarbonise our housing. Hydrogen will play a role in delivering this solution, although at present it seems unlikely it will be the major one. At the same time it is critically important to ensure that all homes become as energy efficient as possible irrespective of how they are energised.
Hydrogen does also offer wider potential in the built environment particularly in its use for transport. It's encouraging to see that Llandrindod Wells based car manufacturer Riversimple have successfully raised £1.5million of funding to support consumer trials for its cars, and this has real potential for a Welsh business to play a significant role in building zero emission cars that will play increasingly important role in our sustainable future.
Wales is also committed to hydrogen research, with the cymruH2wales Hydrogen Centre based at Baglan Energy Park, and supported by Neath Port Talbot Council and the Welsh Government. As we head towards our sustainable future the importance of this type of research can not be underestimated. It will help Wales to unlock the full potential of hydrogen, which in-turn will create opportunities for businesses in the emerging green economy.
Whilst we can’t fully predict the future, we can embrace new green ways of making our future sustainable and at the same time securing our built environment for generations to come. Within this future there will be a range of different sources of energy, including hydrogen, and part of the challenge will be to ensure that we adopt the optimum energy sources in locations across Wales.
