We discussed in our previous article the need to electrify the gas equipment and appliances in the building to achieve net-zero carbon emissions but we noted that the electrical appliances such as the heat pump units for providing space heating are weather dependent and its capacity and efficiency degrade with lower ambient temperatures and it would be better to keep the gas boilers for space heating.

The other option is to run the gas equipment with a clean fuel that does not produce carbon emissions when it burns such as Hydrogen. Combustion of Hydrogen as fuel produces water vapour to the atmosphere and does not produce carbon emissions, which makes it perfect replacement to the natural gas to achieve net-zero carbon emissions.

Countries around the world started trials to use Hydrogen as fuel by mixing it with natural gas in the natural gas network that supplies gas to the houses and businesses. Here in Australia there is Hydrogen Park South Australia (HyP SA) as the first project to mix 5% of Hydrogen with natural gas and supply it to the houses in that district. Also in the beginning of 2022, a 10% of Hydrogen will be mixed with natural gas and supplied to 750 properties in Gladstone (Hydrogen Park Gladston) in Queensland. Most of the modern gas appliances such as boilers are ready to use natural gas with 20% blend of Hydrogen and some manufacturers claim their boilers can use up to 30% Hydrogen blend.

As we can see the use of Hydrogen as fuel started but to reach net-zero carbon emissions, we need to use 100% Hydrogen fuel with 0% natural gas in the gas network, but is this achievable? Is it coming in the near future? Using 100% Hydrogen in our gas networks requires the Hydrogen to be produced at a large scale and in a cost effective way and it requires huge infrastructure to be build. Also, we need the Hydrogen equipment such as boilers to be produced at a large scale to be competitive and adopted in the buildings.

Australian Gas Network who is one of the biggest operator of natural gas networks in Australia targeting 10% renewable gas blending across their networks by 2030 and 100% renewable gas supply by no later than 2050 – and 2040 as a stretch target. Therefore, it is a long way to go until we use 100% Hydrogen in our gas networks. Note that the Hydrogen must be produced using a renewable energy and not using fossil fuels to be 100% Renewable fuel.

Based on the above discussion, we can see that for achieving net-zero carbon emissions in the near future (i.e. short term target), the best option for the building owner is to electrify the equipment and/or buying carbon credits. For a long term target, the building owner might have the option to use Hydrogen Fuel for their gas equipment to achieve net-zero carbon emissions.