Local Power, Local Benefit

managing demand in Berwickshire as a means to maximise renewables generation and minimise fuel poverty

End of Phase 1 LECF Report

Overview

This project, addressing fuel poverty and grid constraints by using efficient electrical heating systems in a demand-side response, will not progress to Phase 2. Although the concept has merit, there are clearly risks in using unproven combinations of technology.

There was a significant change of personnel on the board of Berwickshire Housing Association (BHA—the RSL partner) and the new board was unwilling to commit to what they perceived to be a risky venture for a small housing association and they had particular concerns over the match-funding aspect of the Phase 2 work. They therefore withdrew their support for the second phase of the project.

The remaining partners had discussions with two other RSLs with property in the ARC area to see if the project could continue with a different complement of organisations. Given the tight time constraints, it proved unworkable to pull together an adequate project proposal but discussions are ongoing to investigate these technologies for a future project once time and resources allow. The learning gained during this first phase will be foundational for any future deployment.

Phase 1 activities

The following activities were identified for Phase 1:

The project will build on an existing small scale pilot undertaken by Berwickshire Housing Association where controllable heat batteries and heat pumps have been installed into 6 social housing units. It is proposed that the same equipment is retrofitted with a communications and control system to enable more dynamic control of the operation of the heating systems.
Detailed electricity and heat demand data for domestic properties will be collected and modelled to determine the number of properties required for a 1MW DSM resource.
The generation profile or the output data from a new wind farm installation at Ferneylea will be used to create a model which allows a more detailed understanding to be gained of how output from this wind farm and others in the area could link to demand-side (heating) requirements at a local level.
Ongoing discussions with the DNO who is supportive in principle of the proposal.
Engagement with Our Power and other licensed suppliers to determine the opportunity for a bespoke ‘wind 2 heat’ tariff to maximise the impact of this project.
Consultation with tenants who may be in receipt of new systems.
Review scope for innovative use of solar PV installations in local load management.

Progress and learning

The work carried out and the lessons learnt for each of the activities is detailed below:

The project will build on an existing small scale pilot undertaken by Berwickshire Housing Association where controllable heat batteries and heat pumps have been installed into 6 social housing units. It is proposed that the same equipment is retrofitted with a communications and control system to enable more dynamic control of the operation of the heating systems.

A communications system was identified—V-Charge. They function as an online aggregator and controller. Discussions with the company identified two possible approaches, namely adapting the extant V-Charge hardware controller to handle the larger mains current for the equipment and possibly adding in a modulation signal or integrating the V-Charge receiving and reporting software into the extant Sunamp controllers on the equipment.

Neither route proved to be straightforward and V-Charge was in the process of re-engineering their hardware controller but not with a view to the modifications that we required.

Towards the end of the project, V-Charge adapted a controller and interface board to provide signals and take measurements from a Sunamp PV unit. This has now been demonstrated and can be developed to incorporate additional functionality.

There is hope that the other RSLs contacted during this project will be in a position to take forward the idea and build an aggregated DSR unit controlled through the V-Charge system, supplying valuable grid services at local, distribution or wider level.

Detailed electricity and heat demand data for domestic properties will be collected and modelled to determine the number of properties required for a 1MW DSM resource.

A 16-channel monitor was used to measure temperatures of one of the installations in a detailed way. This gave good insight into the thermal dynamics of the system in a real-life situation.

Detailed case studies were written up for the six trial installations and presented to the BHA board. (attached)

Although the units are demonstrably more effective and cheaper than any of the previous heating systems, the board were unwilling to move ahead with a broader implementation of this technology and the DSR aggregation that would move the benefits to the next level.

The generation profile or the output data from a new wind farm installation at Ferneylea will be used to create a model which allows a more detailed understanding to be gained of how output from this wind farm and others in the area could link to demand-side (heating) requirements at a local level.

Historic wind speed data and output data from an extant wind farm were both modelled to produce an anticipated output from the Ferneylea wind farm. This was compared to the available capacity on the circuits as recorded and modelled by SP Energy Networks to give a matrix of curtailment over a 2½ year period. This was then analysed to draw out patterns and aggregate figures.

The main finding is that although curtailed periods fall mainly within the heating season and as such provide a good match for the DSR systems envisaged, this curtailment itself would be insufficient to provide all the necessary power unless inordinately sized heat stores were deployed.

Other mechanisms of DSR were also looked at (see 7).

Ongoing discussions with the DNO who is supportive in principle of the proposal.

We have held five round-table meetings with SP Energy Networks, the project partners and University of Strathclyde (an ARC partner) as well as copious email exchanges and phone conversations. They have been thoroughly supportive of the project and committed significant resources to it as it falls within the ARC (Accelerating Renewable Connections, LCN Fund project) area.

Engagement with Our Power and other licensed suppliers to determine the opportunity for a bespoke ‘wind 2 heat’ tariff to maximise the impact of this project.

Early discussions with Our Power revealed that they might not be fully functioning by the time that the project needed the special tariff although they were very willing to look at ways of achieving what the project is aiming to do through such a commercial mechanism.

We therefore approached other suppliers, who were also open to the concept although none of them have an extant tariff that fits the brief. Due to the large amount of work involved in pulling together such an offering, most suppliers wanted a minimum number of enrolled customers to enable the economics to work. This is likely to prove a significant hurdle, particularly with the current regulatory constraints on number of tariffs that a supplier can offer, until the model is established.

Consultation with tenants who may be in receipt of new systems.

The consultation with tenants was held off until the situation was clear enough to avoid too much disappointment and falsely raised expectations. As it turned out, this proved to be prudent given that the housing association decided not to go through with the plan.

Review scope for innovative use of solar PV installations in local load management.

This task ended up being a major focus of the project and huge amounts of work have been done by SP Energy Networks; both the ARC team and their Cities team.

Detailed mapping of each potential dwelling was carried out to identify the particular low voltage (400/230V) circuit that the building is connected to. Each circuit ‘cluster’ was then further analysed to ascertain whether potential generation could exceed voltage or thermal limits.

The PV installers—Edison Energy—supplied historic output data from a number of their previous installations. This was then analysed bythe University of Strathclyde to ascertain maximum generation at different times of day for installations with different orientations. This was then mapped to the selection of roofs in a cluster to produce a maximum aggregated output for the cluster. This robustly demonstrated a significant reduction below the total installed capacity and surplus generation above thresholds was calculated in terms of maximum hours and kWh that would need to be absorbed from the circuit before the power reached the transformer.

These analyses demonstrated that small heat store units could be effectively deployed to prevent problems arising on circuits where the nominal capacity for DG is exceeded by a proposed development. A simple control system would need to be devised to trigger the loads.

Conclusions

The work has demonstrated the effectiveness and difficulty of working together with multiple organisations contributing their expertise and sharing resources and findings.

The ability of an aggregated DSR system to relieve constraint of renewable energy generation is clear and a number of approaches are possible.

There are clearly challenges to be met in terms of providing a suitable scale of controllable load and establishing a demonstration system will be vital in proving the concept and evidencing the benefits.

Creating the right financial model and mechanisms to incentivise participation by the various players is also challenging as the economic benefits are highly sensitive to various factors and some of the feedback mechanisms necessary are not yet in place due to the flat-price structure of domestic electricity supply and the restrictions of the electricity supply regulations.

The work on the PV installation clusters is going ahead anyway and the impetus from this project has helped enable that. The first list of ‘green to go’ properties is being installed now (February 2015) and the next level of analysis is being carried out to enable the next tranche to be cleared.

Attached

Report from University of Strathclyde

Six (6) case studies on heat battery installations