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Decarbonisation of micro-homes

As part of the Eastern New Energy (ENE) project, ARU academics and students supported a micro-home charity to decarbonise their units for the recently homeless. They also helped maximise the potential number of sites the optimised units can be installed on, increasing the enterprise's output and turnover.

Logos for ARU, University of East London, Eastern New Energy, EU Regional Development Fund and HM Government

The Eastern New Energy project is funded by the England European Regional Development Fund

The objectives of the collaboration were to:

  • support the decarbonisation of the existing units to maximise gains and enhance the affordability of the units for their tenants;
  • support the development of an off-grid version of the units, opening the possibility for micro-homes in areas with poor or little utility provision; and
  • develop guidance to support future decision-making concerning micro-homes.

The original carbon footprint

Autumn/winter data from a pilot site showed median energy consumption for the units was, on average 6.73kWh per day, covering all electricity provision for the units. This calculation uses the SAP 10,1 UK grid carbon factor for electricity of 136 grams CO2e/kWh.

Sustainable technology evaluation

The following were identified and evaluated as potential routes to decarbonisation of micro-homes:

  • the unit fabric
  • solar panels and wind power
  • liquefied petroleum gas (LPG), BioLPG, and space heating
  • ground source heat pumps
  • air source heat pumps
  • solar water heating
  • radiant heating (wet and dry systems)
  • combined heat and power boilers


In line with the fabric first approach to decarbonisation of the micro-home units, energy conservation should be prioritised over the addition of new low-carbon technologies to the current build system. It was therefore suggested that the insulation used in the units be reconsidered and increased.

The panels could also include the radiant heat options to reduce the running costs of the units, especially if a wet system is used. This would also remove the need for the mechanical ventilation with heat recovery system (MVHR) and electric radiators, and provide a heating system that would improve occupant comfort at low energy input levels, and ultimately influence occupant behaviour.

A further option was that of solar thermal which, although unlikely to be able to support both hot water and radiant heating, could reduce the electricity consumption of the units overall. However, this would require backup systems, as it cannot guarantee supply all year round in the UK.

The UK Grid is one of the most decarbonised in Europe, and so is a logical choice for neutral market facilitator (NMF) for energy input when the current costs of sustainable technologies are considered. For off-grid sites, however, heat pumps and photovoltaic technologies (PVs) become a viable alternative. The permanence of the sites would influence the type of pump employed.


The information in this article is based on academic research, developed in conjunction with students. The information provided is underpinned by research, but please note that suggestions and recommendations remain theoretical. The micro-home charity was strongly advised to consult with appropriate certified/technical specialists to explore firm cost implications and design details before implementing any of the recommendations in their units.