The deliverable D4.11 Limerick DPEB Implementation Guide 2 was submitted by MPOWER, LCCC, GKINETIC, IESRD, ESBN, and ESB in October 2023 with contributions from UL, SE, LCEA, and NTNU. The executive summary of the deliverable is available below and the full deliverable is at the end for download:
“This report chronicles the efforts of the Limerick partners within the +CityxChange project to develop a distributed Positive Energy Block (DPEB) based in Limerick city centre. For a group of buildings to become a distributed Positive Energy Block (DPEB), the main requirement is to reach a positive energy balance across the selection of buildings. This means reduction of energy demand and increase of local renewable generation. These buildings also require a means of energy “connection” so as to allow a local energy market. In Limerick, this was to be provided by a Community Grid, which would enable Peer to Peer trading, within a defined, local area.
This report is the second of two Limerick DPEB Implementations Guides. The first one (Deliverable D4.4 Limerick DPEB Implementation Guide 1) reflected the situation after the first two years of implementation and this one describes the situation after the end of the extended implementation phase, after year 5 of the project.
It was recognised at the start of the project that the city centre location, the heritage protection and traditional construction of these buildings would limit the amount of interventions for energy efficiency improvement and Renewable Energy (RE) generation potential that could be done directly with the buildings. This meant that the DPEB was designed to rely on external renewable energy generation to reach a positive energy balance and this renewable energy generation was identified as the Tidal Turbines, to be deployed in the river adjacent to the PEB.
An early learning from the project was the need for other RE generation assets, in addition to the Tidal Turbines, labelled “Independent Renewables”, to allow for a DPEB positive energy balance. While ultimately the efforts to achieve a positive energy balance in the Limerick Distributed Positive Energy Block (DPEB) is still a work-in-progress, a number of changes and mitigations were developed and tested.
This general process of developing a positive energy balance was outlined earlier in D4.4 as: Record – Plan – Implement – Integrate – Optimise and Balance; and the project’s efforts in driving this process are documented in this Deliverable. Efforts to promote the retrofitting of the DPEB buildings continue; a proposal for specific grant funding, paid through a bespoke Retrofit Pilot Programme, is under consideration with the Sustainable Energy Authority of Ireland (SEAI). This retrofit programme includes a Deep retrofit option, which allows for the installation of heat pumps, replacing natural gas boilers. The process of installation of Building Integrated Solar PV has become easier, with the regulatory and support environment much improved over the lifetime of the project. Discussion with the DPEB building owners is ongoing, with the expectation that solar PV will be added to any deemed suitable. The installation of the first phase of the tidal turbines awaits the passing of the final hurdle, the issuing of a foreshore licence, with the efforts to promote a community group to develop and own Phase 2 of the tidal turbines ongoing. The preferred ownership model for Phase 2 is through a Renewable Energy Community (REC), which will be enabled through support available as part of the new Small Scale Generation scheme. On the grid integration and active energy management side, the formation of a Community Grid (CG) was intended as a key component of the DPEB formation itself.
SLUs (Smart Link Units) were supposed to be the main hardware components of the system, to collect consumption data from the PEB buildings as smart meters. They were installed in the first five PEB1 buildings to get an overview of real-time electricity data, instead of previous monthly or yearly data from energy bills. Beyond that, and regarding enhanced technical functionality, the tech partner encountered procurement and technical challenges.
Engagement of the DSO to allow the formation of a local CSO to manage the selected portion of the grid is crucial for full implementation of the Community Grid concept. Since this didn’t happen, a virtual version was proposed instead, with energy trading to be modelled based on the real time data received from the SLUs. This alternative work was limited; the initial status is described in the related energy system reports (D4.12 etc.).
Regarding this community aspect, an alternative has been found in the possible form of a REC (Renewable Energy Community) that is being followed up by the partners and the city also after the formal project end, to ensure this work will bring results for Limerick. The evolution of Renewable Energy Communities (REC) may provide a lasting model for DPEB creation; by both providing the additional renewable energy generation by larger but local sources, therefore achieving a positive energy balance and allowing the REC members to be connected by the sharing of the electricity produced.”