Research indicates Irish energy policy in its current form priorities high-income cohorts in society, write Juan J Cuenca and Barry Hayes, University College Cork. 

A conversation about our transition towards a decarbonised and sustainable society usually starts with the need to produce clean electricity. There are different technologies and scales for this: from residential or small-scale projects like installing solar panels on your roof (that we will call customer-sized projects), to remote large central generation plants such as offshore wind and large-scale solar farms (that we will call utility-scale projects).

Limited grid availability

Each of these technologies and scales have their advantages and technical challenges, which inevitably come with a few compromises. One of the least-discussed has to do with limited grid availability: who gets to install renewable energy projects – and who does not?

The Irish grid does not have unlimited capacity to connect renewable energy projects: too many of these can result in large, reversed power flows that may cause power line overheating, as well as overvoltage, protection and substation issues.

To prevent these issues from appearing, ESB Networks (being responsible for managing the grid safely and reliably) publishes a network capacity map showing how much capacity is left anywhere in the grid for new generation projects. From RTÉ Radio 1's Countrywide, visiting a sheep farm in Co Wicklow that recently became the first Irish solar farm to connect to the grid. 

As a potential future owner of a customer-sized project, ESB Networks requires you to check the capacity map, and to make contact to discuss the alternatives if there is no availability in your substation.

From 2021 figures in the capacity map we estimated that overall, there are between 3.2 and 10.4GW available to connect these type of generation projects to the Irish grid (depending on where you connect a project there will be more or less grid availability).

Since outside of utility-scale projects, Irish energy policy categorises renewable projects by scale as microgenerator (for sizes up to 11 kW), minigenerator (for sizes up to 50 kW), and small-scale generators (for sizes up to 200 kW) we can do some rough calculations. In the worst case, grid availability is enough for 290,000 microgeneration projects, 64,000 minigeneration projects, or 16,000 small-scale generation projects – or most likely a smaller combination of these. Grid capacity is then sufficient only for a fraction of ESB Networks' 2.4 million electricity customers to install renewable energy projects.

Already reached the profitability sweet spot

It is important to acknowledge that installing a clean generation project of (almost) any kind and scale has already reached the profitability sweet spot in Ireland: lower prices of installation, government grantstax incentives and the clean export guarantee make renewable energy installations a safe and profitable investment.

But if these projects are economically so attractive and there is limited grid capacity for them, who gets the privilege? And can this be done fairly? Our research group at the School of Engineering at University College Cork looked at technical information from the grid, energy policy and customer demographics at a national scale in search for answers.

Our research suggests that Irish energy policy in its current form is expected to give priority to high-income portions of society. Our projections show that early birds (generally well-off households and businesses) will take most grid capacity.

This phenomenon has already been documented in grids from CaliforniaSpain and Germany. In parts of their grids, most capacity (together with subsidies, tax exemptions and economic benefits) has been already taken by wealthy installers, leaving low-income portions of society with significantly less access to clean energy generation projects. This is sparking concerns of future energy poverty.

If we continue this path on the island, the privilege of owning a renewable energy installation (with the associated government grants, tax exemptions and earnings from selling electricity back to the grid) will be mostly reserved for those already privileged, enhancing existing inequalities.

In our research article we suggest that considering grid capacity as a shared resource may be a solution, and we propose two key modifications in policy to prevent grid access inequalities from emerging.

  1. Instead of blanket capacity limits (eg, 11kW limit for microgeneration projects), it is necessary to conduct detailed technical analyses of the infrastructure to determine the maximum capacity of renewables that a customer can have without affecting others. In other words, making the estimation of individual capacity their 'fair share'.
  2. Accepting that some households have financial means to install more and install earlier, we suggest the inclusion of compensation mechanisms that allow these households to pool other parties' 'fair share' in exchange of financial benefit coming from the pooled capacity. 

Projected installation sizes of rooftop solar PV in 30 years in Ireland under current policy. Map supplied by authors.

Community-owned renewable energy projects that have increased participation levels per kW installed, investments in infrastructure upgrades (there are several major transmission and distribution upgrade projects planned to be delivered before 2030), and energy storage projects to increase grid capacity are good alternatives to tackle this problem, but these come at significant financial costs.

Our research calls for a larger emphasis on equitability concerns in grid capacity assignment for renewable energy projects through simple modifications in policy. After all, the conversation we started with was about decarbonisation and sustainability, and the UN's Sustainable Development Goal 7 calls for affordable, reliable, sustainable and modern energy 'for all'. 

Projected installation sizes of rooftop solar PV in 30 years in Ireland with capacity availability as a shared resource. Map supplied by authors.

There is consensus on the future of the energy sector being a combination of clean electricity generation from different technologies and scales, flexibility from customers to use that electricity as it becomes available, means to store some of that energy for later use (to avoid too much of it going to waste), and a robust electricity grid that puts all of that together.

With our research flagging new equitability concerns, technological advancements and the political will for decarbonisation need to be complemented with socioeconomic equality concerns.

Authors: Dr Juan J Cuenca is a researcher in electrical engineering, at the School of Engineering and Architecture, University College Cork. Dr Barry Hayes is a senior lecturer in Power Systems Engineering at UCC. This article first appeared on RTÉ's Brainstorm.