Sustainable energy for the island of Inishmore with a community microgrid: Part 1

Last updated: 29th September 2022

Ireland’s climate and energy ambition is reflected in the Government target set under the Climate Action Plan 2021 to increase the proportion of renewable electricity to up to 80% by 2030.

The Aran Islands Energy Co-Op aims to decarbonise the islands (including Inishmore), generating their own electricity and giving more autonomy and control to the islanders over their energy supply. The Aran Island Energy Co-op was established in 2012, so is now ten years into an ongoing project to make the Aran Islands fossil fuel-free.

Integrated Environmental Solutions (IES) are supporting them with a comprehensive research study, using smart, sustainable ICL Digital Twin technology to support a microgrid.


Inishmore is a small island off the west coast of Ireland with between 800 and 900 inhabitants. Tourism is their main industry in the summer months and it is a very popular holiday destination. The community has a strong history of self-sufficiency, so the majority of islanders were receptive to the idea of establishing a peer to peer microgrid, to generate, use and trade their own, clean energy. They no longer want to be so reliant on carbonised energy from sub-sea cables. The island provides an excellent pilot site for abstracting the national grid at a neighbourhood scale.

Peer to peer trading

There is a paradigm shift for climate change – many communities like Inishmore are looking to generate their own sustainable electricity locally, then distribute any surplus back to the national grid. This process of decentralising energy production, using locally sourced energy, is part of a national effort to clean up the grid.

Peer to peer (P2P) trading involves trading electricity with neighbours, as opposed to the grid, and is a very complex undertaking. The new system focuses on decarbonisation, using PV panels, wind turbines and storage devices, coupled with smart meters which informs P2P software the current state of the local network. When energy is being over produced at one building, the P2P software redirects surplus energy to a neighbouring building that can use it, otherwise, the energy is stored for later use or sold back to the grid.

However, to make the local grid versatile enough to enable two-way P2P electricity, it needs to be adapted, with stabilisers, so as not to damage the network. From the 1970s onwards, electricity was produced from diesel generators on the islands. The electricity cable from the mainland was laid in the early 1990s, originating from a power plant in Galway, which was transported under the water and into homes via the national grid.

The Aran Islands Energy Co-op is 100% community owned and regulated by the registry of friendly societies, whose objective is to have the infrastructure and software in place to control their own energy supply and consumption in the future. There is currently a 3MW sub-sea cable coming to the island, and the 2018 Energy Masterplan showed that 52% of electricity that comes from the mainland is lost in transmission, which is a massive waste. If electricity is generated and used locally on the island, every unit consumed would replace more than two which would otherwise be imported.

They wish to use their renewable, clean energy first, then use energy from the grid, if necessary, thereby reducing carbon emissions. If they have surplus energy to sell back to the grid, they will receive it either in money back or credit tokens. Each household will be a producer and consumer, known as ‘prosumers’.

The purpose of energy simulation technology

This is Inishmore’s first attempt at a dynamic energy profile of the whole island. To execute it efficiently, they needed to abstract the system, and do it simply. Bridging the gap between the real world and simulation, the ICL Digital Twin modelling enables the continuous operational optimisation of not just single, but entire groups of buildings.

Creating a virtual network enables the inhabitants to see who is using what energy, and when. It’s a hierarchical decision-making process, where people only use the grid when their own electricity is consumed, for back up, and if there is no wind for turbines, sun for PV panels or stored energy left. In the virtual networks current phase, the energy profiles of the inhabitants are based on estimated energy use, but with the help of smart meter data, the inhabitants will be able to implement a decision matrix, maximising the consumption of localised energy production. Using the information from the virtual network will support the creation of a P2P network on the Aran Islands.

ICL Digital Twin technology for Inishmore

IES were brought on board to conduct a detailed field survey, including a stock take of the levels of insulation, heat pumps and PV solar panels in the island’s houses, then log the data into the ICL Digital Twin platform.

It had been hoped that the inhabitants could hand over accurate data from their smart meters, but the supplier setting up the infrastructure, implementing the stabilisers and installing smart meters has had logistical issues with the Covid-19 pandemic, access and supply chains, so the smart meter installation has been delayed.

Inishmore does not have Google Maps Street View, so Niall Buckley, IES’ Project Manager, had to carry out a painstaking, manual assessment of 706 buildings and houses, to assess the archetype of each building. The data was input to the ICL Digital Twin modelling software, which created an energy simulation profile.

IES and CFOAT also conducted a survey of as many inhabitants as possible to ascertain the building construction date and any renovations: the accuracy of this data is key as it has an impact on energy performance. The responses and the initial survey agreed on 80% of the building attributes mapped which was not too bad, when taking a holistic view of the whole island, and considering that prosumers often mistake the age of construction.

Promising results

The Digital Twin model is now up and running, which is providing a comprehensive baseline of Inishmore’ energy consumption. A Regional Building Energy Consumption model, based on the visual cues, can now be used to provide Estimated Energy Performance Certificates (EEPCs). It is still at the calibration phase, and vacant or uninhabited houses have to be removed.

With the simulated data in place, hypothetical analysis can be created with IES software, giving the Inishmore residents a great tool for planning ahead. They can produce hypothetical scenarios, such as adding 20 new electric vehicles, 50 more houses with PV panels and 30 more heat pumps, to see what difference it makes to energy generation and consumption.

On the heating front, they are slowly upgrading all 500 homes and other buildings on the island. A few hundred homes are retrofitted, some to a very high level, and more are planned. Retrofits include external wall insulation on the older homes, heat pumps for hot water and heating, and solar PV panels on the roofs.

With the community planning to set up a microgrid, they can pool excess electricity, sell it to their neighbours and even back to the grid. The tourism industry on Inishmore is booming in the summer, when there is not much wind, but that’s when the PV panels come into their own. If the wind power in the winter months is not consumed during off-peak hours, they can store the excess power for use during peak times or sell it back to the grid.

“Heat pumps and PV panels are a substantial investment and you can understand the possible reticence of some inhabitants to make that up-front investment. I hope that IES can help facilitate this transition by showing them the benefits of generating clean, green energy and how they can reap the rewards if they have excess to sell on. You can’t improve what you can’t measure, and with the Digital Twin model up and running, it is providing a comprehensive baseline of the island’s energy consumption.”

–          Niall Buckley, IES Project Manager

Ongoing studies for further accuracy

IES have performed an iteration of the study on 90 houses, with residents’ participation, whose data seemed quite accurate; 25 of them already have smart meters and PV panels installed and none of them have wind turbines. The ICL Digital Twin technology has proven that residents will gain maximum benefit if they put PV panels on their roofs.

They also want to install a community turbine, which may result in more electricity than they need. However, the beauty of being able to model it means that with the profiling, it’s very easy to visualise the predicted energy generated and consumed on the island.

“Niall presented the Digital Twin technology model to the islanders and explained it very well, in layman’s terms. It was great to be able to show them the interactive technology, and how they can add more energy-generating tools with a hypothetical scenario.

IES have been fantastic. They have vast expertise and understood the importance of continuity at the start of this ambitious research project. They are extremely patient and considerate to the fact that Inishmore is a small community, and they have taken on board all the residents’ feedback, always aware of the human element involved: this project is peoples’ lives! They really have gone above and beyond and spent a lot of time talking the results through with me and the Co-op as a whole, to achieve the best possible outcome.”

– Avril Ní Shearcaigh, Project Leader for Aran Islands Energy Co-Op

The pilot project to create a peer to peer trading network of microgrids, in collaboration with IES, can be used as a blueprint in the future for any other community, large or small.

This project is still in it’s final year. Once complete we intend to produce a follow up in way of Part 2 of this case study to showcase the final conclusions of the project.

This project has been supported with financial contribution from Sustainable Energy Authority of Ireland under the SEAI Research, Development & Demonstration Funding Programme 2019, Grant number 19/RDD/532.

N.B. The information contained in this entry is provided by the above supplier, and does not necessarily reflect the views and opinions of the publisher

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