Solar power generation tends to invite jokes about the Irish weather but, says Bridget Ginnity, it can make a significant contribution domestically and industrially to Ireland’s renewable energy goals

ONE of the incredible success stories in renewable energy is how the price of solar PV (photovoltaic) panels has plummeted. Solar power generation is now cheaper than fossil fuel generation, with India and China leading the way.

In Clare, we have more wind than sun, and the energy generated by a wind farm is about ten times that of a solar PV farm over the same area. Ireland has among the lowest solar generation capacity in Europe, with at present less than 0.4% of electricity generated by solar.

However, solar energy generation is an important balance to wind for those calm, sunny periods. Also, it’s much more feasible to generate energy from solar panels on a small scale and at the domestic level.

Shouting from the rooftops

Looking around the rooftops in Clare, we can see more and more people are generating their own electricity, and Eirgrid hopes to see that number rise. They are planning for about 150,000 houses or other small installions to give a capacity of 600MW.

The early household solar panels were mainly thermal, sending hot water into your immersion and central heating systems. Photovoltaic (PV) panels which generate electricity directly are recommended nowadays unless you have an unusually high hot water demand, such as four teenagers in the house.

The set-up is fairly straightforward. PV Panels covering an area of about two car parking spaces generate about 4500kWh or units of electricity a year. That’s about €1,800 at today’s prices. A house from the Bungalow Bliss era is perfect, with plenty of unbroken roofspace. If you have a dormer house, the windows are challenging, but it can be done.

South facing is best but not as essential as you might think, and the angle of the roof influences the output as well. Houses with a bit of space around them sometimes opt for ground mounted panels, which are much easier to install. And wherever you put them, planning permission is no longer required.

When the sun shines

We don’t need research projects to tell us that energy is only generated when the sun is shining on the panel. The problem is though, we need electricity when we are at home and when it is dark – which doesn’t always coincide with the sun. The options are selling excess electricity back to the grid for a small payment, storing it in a battery for use when you need it or diverting it to the immersion heater.

Christy Sinclair, a PV installer with Elements Energy, strongly recommends batteries, even though they are no longer covered by the grant. He says it makes the difference between being able to use less than half your electricity to using perhaps 80%. They also mean you are protected against any electricity black-outs that might occur.

On the other hand, sending excess electricity to the grid is much more environmentally friendly than having individual batteries at thousands of houses. Energy needs across the county can be balanced and any excess stored in large battery units on the network.

But decisions like this depend on your individual needs and it can be hard to know what to do. That’s where group schemes shine.

The Meitheal tradition

The Meitheal tradition was alive and strong in the days of turf cutting and hay making when the neighours gathered to work together. Colm Garvey of Clare Energy Community Agency (CECA) is promoting that same approach to getting solar PV in our homes.

CECA supports households in an area to arrange installation as a group. The advantages aren’t just cost, although that is certainly one. Knowledge and experience is shared and it helps you get the best system to suit your needs.

Colm acknowledges that residential solar systems are less cost effective to install and to run than large solar farms but he suggests that a very direct benefit of rooftop installations is the way they change behaviour.

“When we have a system in a home or school, people see the link to energy and that has a huge impact. They become much more energy aware and energy efficient. Changing people individually in this bottom up approach normalises renewable energy, and helps it spread,” he says.

He is optimistic about the proposed support scheme for Small-Scale Generation (SSG). He thinks it will have the benefits of lower cost, greater efficiency and still be tied in to communities and behavioural change.

He’s probably right about behavioural change – a common trait among the householders with solar PV is that they can tell you how long the sun was shining for every day last week!

What’s the payback?

With the current price of electricity, the payback time for a typical solar PV system is getting shorter and shorter; now it is about six years.

And the beauty is that you can make savings of about €1,500 a year after that. The cost for a 5kW system with battery is about €9,500, after the maximum grant of €2,400. And farms and small commercial properties are now covered by the grant.

So if you can get the funds, it certainly makes sense financially. But when we talk about investing in a solar PV system or any other way of reducing out carbon emissions, do we put too much emphasis on grants and payback time?

These are important but for some reason, we don’t apply the same decision criteria when we are buying a car, holiday or a new kitchen.

Perhaps that’s because the benefit of reducing carbon emissions isn’t immediate – although a free 15 minute shower is pretty good. But the real payback for any action needs to be kept in mind – a planet that our children can live a good life in.

So even though budgets are tight and getting tighter, perhaps we need to spend our children’s inheritance now on climate actions so that they have a decent world to inherit.

Is bigger better?

Some planning applications are under consideration in Clare at the moment, including two of almost 30 hectares, one by Renewable Energy Systems near Clarecastle and another by Reeve Wave in east Clare.

These offer economy of scale and in one fell swoop the two farms would generate the same electricity as putting solar PV panels on about one quarter of the houses in Clare.

The Clare County Development Plan includes a target of 300MW utility scale solar farms “in appropriate locations throughout the County including on agricultural lands and brownfield sites”.

This would occupy a little over 400 hectares of land and reduce carbon emissions by 80,000 tonnes. Planning permission has been granted for a total of 13 solar developments in Clare which would generate about 100MW.

But the very scale can cause difficulties for people living in the locality and leads to objections.

An underlying concern is that a large scale solar farm is out of character for a rural, farming area. Yet it has been found that solar farms can work well with some types of farming.

Sheep are a low cost way of keeping the grass under control and the farmer is provided with grazing land. Lots of research is underway about other happy co-locations of solar and agricultural farms and of course, it’s very wild-life friendly if the land is let go back to nature.

Most objections refer to visual amenity and glare. There is a standard way of assessing glint and glare and identifying houses that may be adversely impacted, depending on the distance and angle.

Assessment reports indicate that the impact on locations most affected can be mitigated – and the most common mitigation measure seems to be to plant a hedge.

Other grounds for objection include things like noise, pollution, construction disturbance, security and so on. These are similar to objections that some people living along the routes of motorways had and living near a motorway can certainly be noisy and polluting – significantly more than a solar farm.

Yet many of us appreciate that the M18 went ahead and we’re not sitting for half an hour in traffic in Newmarket-on-Fergus.

Similarly, it’s necessary to balance the drawbacks of solar farms with the benefits of reducing fossil fuel use.

Conventional power plants generate significant pollution and noise and by far the biggest problem is that their carbon emissions are destroying the climate.

And do we want to be buying gas from Russia and oil from Iran in 20 years? Energy security and lower electricity cost due to renewable energy will bring huge benefits to Ireland.

Nevertheless, we can’t expect people in the locality to pay an unreasonable price for the common good. The best outcome is when we mitigate the adverse impact of solar farms for people in the locality and compensate for any residual impact.

What’s the alternative?

It is completely understandable that when you are used to looking at a swathe of green fields that the prospect of shiny surfaces from solar PV panels is unpleasant.

While we need to get moving on current projects as quickly as possible, it’s worth considering some alternative location types for solar farms where there is the advantage of scale without the disadvantage of disturbing pristine areas.

What we need are large open areas which are already impacted or are brown field sites, and are close to the distribution network. Sites like the county council car park perhaps?

A carpark with 150 spaces will generate up to 500,000 units of electricity a year. That’s about €200,000 worth of electricity at today’s prices.

A quick scan of larger Ennis car parks shows an available area of about five hectares, which would generate about four million units of electricity a year, enough to power over a thousand houses.

They even have the advantage of providing shelter from the rain. The Ennis farmers’ market could finally be covered if the Roslevan car park became a solar mini-farm!

Large industrial, commercial and farm buildings are ideal for small scale solar PV if they have a large amount of roofspace or yard/carparking area. Locations like the Roche site or Gort Road Industrial Estate perhaps.

Small-Scale Generation

Tom Golden in Cratloe has been working for years with the community on a proposal for a 5MW solar farm and has become an unwilling expert in the challenges involved.

Everything from connection costs, supply chain issues and funding is really difficult.

“Most of what was successful at RESS auction [the competitive process to decide what projects are supported] hasn’t been built because you’d lose money.” he says.

He believes the proposed support scheme for Small-Scale Generation (SSG) that is in development is a much more promising approach for community projects.

They are smaller scale, typically 100-200kW, and so they don’t have the high costs of new grid connection.

“In SSG, communities are producers and consumers of electricity and it promotes self-consumption first. The real aim is that we moderate our use, using it when it is renewable,” says Tom.

“What we need for it to be viable for communities” he adds, “is a national procurement agency and national funding agency. We don’t want to see communities competing against each other.”

In another community type scheme announced in the budget, free solar PV panels will be provided for every school in the country.

Perfection is the enemy of the good

Everything we’ve talked about here has drawbacks. Household rooftop isn’t the most cost effective; community engagement takes huge voluntary effort; large scale projects have visual and other adverse impacts.

Even producing panels and batteries cause harm on the environment. No project is perfect. But every project helps to reduce carbon emissions.

If we delay and wait for the perfect project, it’s like waiting for the perfect love match. It may never happen. Waiting for the perfect match can end in a solo life. Waiting for the perfect project can end in climate chaos.

We are no longer the teenager who has time on their side to select a mate. Action, any action, is needed now.

That action can take various forms. Some of us can install solar PV at home, or work on a community level. Others with funds available can invest in renewable energy companies, or perhaps fund a family member to install solar PV – a perfect wedding present. And we all have a voice in supporting projects in our locality and ensuring they are done properly. We all can make a difference.

Which panel is which?

The term ‘solar panel’ is often used interchangeably to describe the panels that generate electricity and those that generate hot water.

Solar panels that produce electricity are known as solar photovoltaic (PV) modules. Solar panels that produce hot water are known as solar thermal collectors or solar hot water collectors.

A 5kW solar PV system requires an area of about 25 m2.

This would generate up to 4,500kWh (units) of electricity a year, which is about €1,800 at the current rate.

Solar panels generate energy during daylight hours only, predominately around the middle of the day. While clouds reduce the output, the panels still generate useful electricity on an overcast day (the energy yields mentioned in the article are for Irish conditions).

Surprisingly, certain cloud formations can boost output, called the cloud edge effect. When the sun appears at the edge of a cloud the panels receive direct sunlight and also diffuse sunlight via the clouds. In Ireland, around 75% of the energy from solar panels is produced from May to September, so it’s very well suited to a tourism business.

The grant available for domestic, farm and small business installation is €900 per kW up to 2 kW, with an additional €300 for every additional kW up to a maximum of €2400. In other words, it’s grant aided up to 4kW.