The 2019 amendment to the Climate Change Act commits the UK to reduce its greenhouse gas emissions to Net-Zero by 2050.  To achieve this there must be a step change in the way we heat our businesses, public buildings, and homes. The heating industry, government and the public must work together to innovate, legislate, and acknowledge the change that is required to drive towards NetZero.

One of the largest sectors of the decarbonisation challenge will be the preparing the existing building stock for low carbon heat, of which 80% will still be in use in 2050.  When dealing with older and less thermally efficient buildings, the technically and economically viable solutions become restrained.

Therefore, at Rinnai we believe that a mix of different technologies and energy vectors will offer a combined solution to the challenge. These will ultimately include:

  • The decarbonisation of the gas grid – moving towards Hydrogen.
  • Heat Networks in high populous regions.
  • Heat Pumps for well insulated buildings where technically practicable.

85% of UK homes and buildings are reliant on the natural gas grid for hot water and heating. The continued repurposing of the gas grid to transport greener gas established a low disruption option towards decarbonising the existing building stock. 
Hydrogen is an energy carrier which can be created at volume.  Both blue and green hydrogen offer zero carbon heat at the point of use. Blue hydrogen is produced from natural gas, usually via steam-reforming, with carbon capture storage (CCS).
Green hydrogen is produced using renewable electricity for electrolysis, to separate water into hydrogen and oxygen. Government plans for Hydrogen include utilising both these routes for the future decarbonisation of the gas grid as will be noted in the forthcoming Hydrogen strategy. 
Rinnai Hydrogen Appliances – we are developing and testing water heaters to run on extensive Hydrogen blends and 100% Hydrogen. We are at the forefront of this exciting new technology.  The Rinnai Group have multiple Hydrogen appliances on test across the globe, ready for the adoption of Hydrogen water heating. 

  • Hydrogen ready
  • Zero carbon dioxide
  • Very low NOx emissions
  • Similar installation and commissioning to a conventional water heater meaning - low disruption for consumers.
  • Same compact design and modular capabilities
  • Expansive modulating range

A hydrogen-ready water heater is a hybrid heating system which can burn either natural gas or pure (100%) hydrogen. Hydrogen-ready water heaters are low carbon alternatives which are key to enabling the conversion of the existing gas distribution networks from natural gas (which is mostly methane) to low carbon and Zero carbon hydrogen.

Hydrogen is a carbon-free energy carrier and combustion of hydrogen produces no carbon dioxide at the point of use. Hydrogen is manufactured from water using electricity as a renewable energy source, or from natural gas accompanied by carbon capture and storage.

A hydrogen-ready water heater is intended to provide a like-for-like replacement for an existing natural gas system. The boiler can be quickly and easily converted to burn hydrogen at the time when the local network switches over.

Many existing buildings, despite energy efficiency improvements, still have relatively poor insulation and high rates of air exchange with the outdoors. Whilst also needing high volumes of hot water instantly at constant temperature.

A hydrogen-ready water heater can deal with the existing high temperature heating system in a hard-to-heat buildings and the high demand of hot water continuously without the need for large storage vessels. The water heater (and conversion of the local gas network) provides an accessible way to deeply decarbonise heat.

The water heater is very similar to its natural gas predecessors; it is constructed and functions in much the same way as an existing condensing water heater. While some components are different such as the flame detector, most are identical to those used in natural gas units today. As the flame temperature within the water heater will be very similar to that of a natural gas appliance the reliability of the system is almost identical.

Converting a hydrogen-ready boiler from natural gas to hydrogen will take around an hour and involve changing a couple of components such as the burner. It is envisaged that Gas-Safe engineers will be trained to work with hydrogen by a qualification scheme like that available today for LPG.