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Understanding the changing energy landscape

FIGURE 4 RTN HIGH LEVEL DOWNSTREAM RENEWABLES TESTING OUTCOMES

into a refrigerant fluid, which is then major drawback of fitting a heat pump
compressed, raising its temperature is the requirement for a far greater
further. This fluid is then passed area for radiators. This often must
through radiators inside the property. take the form of underfloor heating,
To design a demand model capable of in practice. The software provides the which is expensive to retrofit, highly
accurately modelling demand based on calculations for house heat loss and rate inconvenient to customers and often
gas usage now and in the future, it was of heat loss from the building based not possible at all, for example in the
necessary to build into the RTN demand on the physical temperatures and the case of smaller flats.
model how these downstream renewables energy balance across the property. In this testing, heat pump technology
perform over a number of conditions, When testing heat pumps, an often failed to maintain the desired
allowing their penetration to be environmental chamber was used, temperature of the property, especially
accounted for when predicting demand. which allowed environmental in high demand, winter conditions.
Therefore, as part of the project, conditions to be mimicked. This allows The inherent issue with a heat pump
laboratory testing of a range of repeatable testing of weather conditions drawing heat energy from ambient
downstream renewable heating to be carried out, something that would air is that when the demand for heat
technologies was conducted. The not be possible in a field trial, unless increases, the very resource it harvests
chosen technologies were: conducted on a very large scale. A total diminishes. This reduces efficiencies
Gas combi boiler of 172 tests were conducted as part of dramatically, as was seen in the results
Air source heat pump (ASHP) the project, with variable load sizes, of this testing.
Hybrid heat pump external temperature profiles, heating As an industry, we must find a way
Gas absorption heat pump (GAHP) modes and radiator temperatures. The to deliver clean energy for heat to
Micro-combined heat and power unit results of this testing were significant consumers in a way that is affordable and
(microCHP) and have been built into the RTN secure. But something this testing has
Laboratory testing was conducted by demand model for scenario modelling. highlighted is the fact that decarbonising
Kiwa Gastec using a dynamic heat loss This testing has outlined how each heat requires a carefully considered
test rig. This test rig can be configured technology has performed when tasked solution for each property type, and not a
to represent the conditions of a large with maintaining a thermostat set one-size-fits-all solution.
range of property types and sizes in temperature in different conditions.
terms of their energy performance. The lower the outside temperature, the SGN’s Real-Time Networks project
For the purposes of this project, the more heat will be lost, and the harder aims to demonstrate how a flexible
test rig was combined with a domestic the technology will have to work. The gas network could be more efficient for
hot water tapping test rig to provide a technologies have been compared, an evolving energy market and meet
continuous hot water demand with the looking at how they perform in different changing customer demands. For more
heating demand, akin to domestic use. sized loading conditions, from a small information visit www.sgn.co.uk/real-
The test rig provides the physical load, which is typical of a small flat, to time-networks
volume of water present in the heating an extra-large load, typical of a very
system and removes the heat that large detached property or a small
would be lost to the atmosphere in commercial premise. References
real operational conditions. Any This testing has proved highly useful 1. Digest of United Kingdom Energy Statistics 2018,
thermostat or similar device is held at to finding a solution to decarbonising BEIS
the correct conditions as determined heat. Heat pumps are undoubtedly 2. Challenges for the Decarbonisation of heat: local
heat demand vs electricity supply winter 2017/2018
by the software model, allowing the effective in a limited range of scenarios, – Wilson et al.
control system to operate as it would namely in new-build properties. But the

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