There is clear scientific consensus that we need to transform our energy systems to reduce greenhouse gas emissions and play our part in limiting global warming to 1.5 degrees. Ireland's climate action plan includes an increase in renewables from 30 per cent of our current energy needs to 70 per cent by 2030. This means more wind turbines, solar panels and crops planted as biofuels. Onshore wind, solar and biofuels will compete with other land uses in Ireland such as agriculture, forestry and habitats rich in biodiversity.
While combinations of land use may be possible for onshore wind, where the turbines take up just 1-3 per cent of the land “footprint” over which they are placed, solar and biofuels are more land-use intensive, with limited room for biodiversity within the farm.
At the same time as having to find solutions to our energy challenges, we are faced with a biodiversity emergency. Eighty-five per cent of our protected habitats are in inadequate or poor condition and a recent Environmental Protection Agency report showed that 43 per cent of our rivershave unsatisfactory biological quality. Nature does not have the capacity to absorb more negative impacts from future developments.
So how do we more than double our renewable energy capacity while at the same time protecting and restoring biodiversity? Climate change is a huge threat to biodiversity itself so sticking with fossil fuel energy and its direct and indirect negative effects of biodiversity is not an option. Reducing our electricity needs through energy-saving devices and behaviours will help; but, given the electrification of transport and industry that is needed, our electricity needs will certainly increase.
Mitigation hierarchy
We need to develop biodiversity-friendly renewable energy by prioritising renewables that are the least damaging and ensure that infrastructure development is carried out as sensitively as possible to protect, restore and enhance biodiversity. The mitigation hierarchy focuses first on avoiding negative impacts and only then minimising harm, remediating damage and, if these efforts are insufficient, damage at the focal site can be offset through biodiversity improvements in another site.
Biodiversity-friendly renewable energy starts with the planning phase where areas at risk of conflict with biodiversity needs can be avoided using sensitivity mapping tools such as those developed by BirdWatch Ireland. Getting the location right avoids impacts on particularly sensitive species such as raptors and bats in onshore wind farms.
The construction phase for infrastructure-intensive renewables (wind turbines, solar panels) can cause habitat destruction and result in displacement, injury or mortality to individuals, which can affect the sustainability of populations if construction covers a large area, occurs at particularly sensitive times such as breeding or feeding, and is long-lasting.
Construction of associated infrastructure such as roads and access areas can fragment the landscape over which animals and plants seeds move, limiting their access to life-supporting resources. Where these impacts are unavoidable they can be minimised through appropriate timing of activities, use of temporary infrastructure and remediation of impacts after construction is complete. An example is the use of “bubble curtains” to limit damaging sound levels from pile driving for the installation of offshore turbines, to protect fish and cetaceans (whales and dolphins).
Ongoing impacts
There can be ongoing impacts on biodiversity such as collision of birds and bats with turbines, inappropriate site management and pollution. Good planning and site management can mitigate some of these impacts and high-resolution monitoring can identify particularly risky times of the season or day where, for example, temporary curtailment of turbine operation can protect at-risk species.
There are potential win-wins for renewables and biodiversity, particularly for offshore wind farms, if appropriately sited outside of sensitive areas. The ongoing operation of the turbines can provide protection of fish stocks from over-harvesting through exclusion of fisheries within the wind-farm boundaries. The “spillover” of healthy fish populations from the wind farm reserves can also benefit fishers, with higher catches reported from areas close to marine protected areas. Aquaculture for seaweed and shellfish can also be co-located with offshore wind farms.
Integrated land and sea use planning will be needed to reconcile competing land and sea uses and achieve the holy grail of “right action, right place” that can minimise harm and enhance biodiversity while maximising our use of renewable energy.
Prof Yvonne Buckley is an investigator in the SFI MaREI project Nature+Energy and based at Trinity College Dublin