LATENT: RESIDENTIAL HEAT AS AN ENERGY SYSTEM SERVICE

The UK's carbon targets, as defined by the Climate Change Act of 2008, specify an emissions reduction of 80% by 2050, which the government has recently revised down to 'net zero' for the same year. In 2017, 17% of the UK's carbon emissions were associated with non-electric use in the residential sector (64.1 Mt CO2), the majority of which were associated with natural gas space heating, cooking and domestic hot water. The UK must therefore decarbonise residential heat to be able to meet its climate change targets, but, in combination with electric vehicles (EVs), this could lead to a 200-300% increase in the UK's annual electricity demand.

In terms of deployment at scale, Air Source Heat Pumps (ASHP) operating either in isolation or as a hybrid gas system appear a key technology as they are not site specific and are applicable to both new build housing and retrofit. The UK's low voltage (LV) electricity network will not however, be able to operate with unconstrained electrical heating or EV charging loads. Both loads must be deferrable or scheduled in a manner to support the electricity network and maintain substations and feeders within limits.

Household electric heating has the potential to operate as a significant deferrable load which LATENT is seeking to understand and harness. This can provide benefits across scales, namely to the UK (energy security and carbon targets), DNO (Distributed Network Operator as grid support), heat pump suppliers (by demonstrating added grid value), householders (in terms of bill reduction and avoidance of peaking dynamic tariffs) and electricity suppliers by applying aggregation techniques to minimise energy service costs.

The key aim of LATENT therefore, is to be able to predict the impact of customers with electrical heating (predominantly ASHP) operating with 3rd party deferrable heating control on the LV network at the feeder / substation level. 3rd party control in this context would be through the energy service supplier, with whom, unlike the DNO, a household has an existing financial contract relationship. LATENT will inform industry of the potential of 3rd party control of deferrable heat through a rigorous field experiment, and, in doing so, accelerate the transition to decarbonised household heating.

LATENT will determine the influence of householder personality trait (OCEAN traits: either positive / negative as Openness, Conscientiousness, Extraversion, Agreeableness, Neuroticism) alongside more traditional Census metrics such as educational attainment, house type etc to deliver a multi-variate regression model to describe deferrable heat reduction at the household level. A substation or feeder can then be analysed in terms of its household type mix (10% C+ detached, 30% E- flat etc) to produce a composite substation level, deferrable heat reduction estimate.

This model will be realised through field trials with LATENT's industrial partner, Igloo Energy. Igloo have a customer base with smart heating systems and ASHP which support remote 3rd party control. LATENT will test (i) householder's stated acceptance to deferral of heating (in terms of temperature drop and duration) through focus groups and surveys, (ii) actual acceptance of heat deferral through heating season field trials, and (iii) operation of a commercial deferrable heat tariff with a sample of Igloo's customer base.

LATENT will create impact across multiple scales (from the citizen to the country) and across multiple sectors (policy, manufacturing, electricity supply, energy retail). These are as follows:

HOUSEHOLD IMPACT (HI)
HI 1. Increased availability of heat as a service energy contracts which incorporate deferral of heat and so lead to a reduction in household bills.
HI 2. Subsidised ASHP system offers start to appear on the market for new customers via energy service companies (such as Igloo) who are able to part finance their packages against the additional value that aggregated heat deferral brings to the LV network. This effect was seen with photovoltaics and Feed-in-Tariff through 'rent your roof' schemes.

SOCIETAL IMPACT (SI)
SI 1. LATENT will support the transition to decarbonised household heating enhancing local air quality and reducing carbon emissions.
SI 2. LATENT will provide a pathway for off gas network households to fuel switch from high cost / high carbon fossil fuels.

NATIONAL IMPACT (NI)
NI 1. LATENT as an enabler of ASHP (or other electrical heating type) at scale in LV networks.
NI 2. Demand Side Management (DSM) becoming embedded within heat as a service provision by energy suppliers.
NI 3. Contribution to decarbonisation of residential heat and delivery of national carbon targets.

POLICY IMPACT (PI)
PI 1. Briefing of Government Scientific Advisors on the decarbonisation of heat challenge and the policy implications of LATENT findings. LATENT will provide valuable evidence of a pathway to decarbonisation of residential heat without compromising the LV network or requiring significant DNO (Distributed Network Operator) investment.
PI 2. LATENT End of Project conference to policymakers and stakeholders.

ACADEMIC IMPACT (AI)
AI 1. 4 High impact journal papers within timefame of LATENT programme
AI 2. Presentation of work at UK meetings, European and International conferences
AI 3. Open access archive of LATENT datasets for future research use via UKDS.
AI 4. LATENT provides academic benefit across four core areas of (i) Understanding of Energy Performance Gap, (ii) Study design and delivery incorporating household traits (iii) household heating behaviour datasets, and (iv) thermal comfort response.

INDUSTRY IMPACT (II)
II 1. Industry awareness (DNOs, technology manufacturers, energy service companies) of the impact of household deferral heat by a 3rd party as an approach to LV support. LATENT addresses one of the key barriers to ASHP (or electrical heating in general) at scale - that winter peak stress on some LV networks will become so severe that a moratorium on heat pump deployment will have to be put in place.
II 2. LATENT will enable the acceleration of heat as a service into the marketplace by building understanding and therefore industry confidence and trust in the approach.
II 3. Development and field testing of a costing framework to deliver deferrable heat in a home.
III 4. Understanding of how household personality trait (OCEAN positive / negative) impacts on 3rd party intervention in the home, wider implications to the energy industry.