A Beginner’s Guide to Solar Energy in Ireland

Solar energy is an increasingly popular choice among Irish homeowners and businesses.

The energy source itself is free and can be utilised anywhere the sun shines and with the progression in solar technology over the past decade, that even includes the year-round Irish climate!

With falling costs and more varied market choice than ever making us a viable nation of solar energy consumers, there are, however, some obstacles to overcome if we’re to truly embrace solar on a national scale.

Harnessing just a tiny fraction of the sun’s energy to convert it to home-consumable heat and electricity is a pretty complex process; you need the right equipment, systems and design infrastructure to leverage solar energy effectively and of course, that initial installation outlay comes at a short-term cost.

In this guide, we’ll bring you through some of the core mid to -long-term benefits of embracing solar energy to help reduce carbon emissions and protect our environment whilst dramatically reducing your energy bills.

We’ll also answer some common queries we receive in relation to our solar energy services and at all times aim to educate, inform and guide you along the path to solar should you choose to opt for this unique form of renewable, green energy to power your house.

Cartoon houses with rooftop solar panels on a sunny day

What is Solar Power?

Solar power is the energy converted from sunlight into usable electricity.

Sunlight is harnessed directly through the use of solar panels. Solar panels are made up of a transparent photovoltaic (PV) glass as well as PV cells which are responsible for converting sunlight into electricity.

The sun’s power can also be harnessed as thermal energy via the use of concentrators and reflectors. Energy harnessed through solar panels can then be used to provide electricity for residential homes as well as powering businesses of all sizes nationwide.

Thermal energy has various everyday uses such as heating homes during cold weather or the solar heating of water in place of traditional gas boiler and immersion systems. Other popular applications of solar energy among Irish solar consumers include powering security and lighting systems, electrifying fences, and aerating garden ponds, among others.

Young family with solar panels

How Does Solar Power Generate Electricity?

Once fitted, the solar panels on the roof of your home are connected to other devices for complete energy generation throughout your home.

When sunlight hits the solar panels, electronic flow is activated in individual solar panels, the resulting electric current is referred to as direct current (DC). The electricity used to power our essential electronic properties such as the charging of electric vehicles, lighting of houses and powering our computing and entertainment systems, is usually in alternating current form (AC)

Thus, the DC electricity generated by the solar panels needs to be converted into alternating current to make it applicable. The conversion of DC to AC power is carried out by a device known as an inverter. This device can be configured into three distinct forms; as a string inverter, power optimiser, or as a micro-inverter.

The two main types of inverter are string inverter or hybrid inverter there also micro inverters that fit on each individual solar panel, but they are less popular in Ireland.

Single string inverters convert DC to AC and feed the house requirement including an immersion diverter if fitted any surplus energy is sent back to the grid.

Images showing the typical energy flow of Solar PV.

Hybrid inverters employ AI to sequentially deal with the electricity demand for the home. The electricity produced will fully satisfy the demand for the house excess powers will be fed to the battery storage and may be further diverted to water heating or car charging.

This will ensure optimum use of all solar electricity generated with any remaining energy flowing back to the grid.

However, the bulk of the work remains to convert energy output from DC to AC (bear with us!).

Once electricity has been generated by the solar panels, it flows via the inverters and is converted into AC power. After conversion, electricity flows to either electric loads or power meters which measure the amount of power generated, depending on the type of inverter fitted.

The energy generated can either be used to power appliances directly, stored in batteries, or sent back to the power grid for distribution into other places. The standalone solar energy systems more commonly found in Ireland may use batteries for energy storage.

Almost all systems installed in Ireland are grid connected as a solar system will rarely deliver the full electricity requirement for a home for a full year.

Less commonly used, a grid-connected system utilises the grid system as the energy storage as well as the power distribution system, however within the next year Irish consumers will benefit from a feed in Tariff to the grid (June 2021 TBA) which will make this type of system more attractive.

Components of a solar power system

Solar Power System House
Solar panels

How Does a Solar Hot Water Heating System Work?

Thermal Solar utilises evacuated tubes technology to exclusively heat water and can generate up to 70% of your hot water needs from free solar energy. It works as follows:

  1. Solar energy is absorbed by the dark coloured absorber and transferred to copper pipes that contain a fluid.
  2. The pump station circulates the solar heated fluid back to the hot water tank.
  3. Throughout the day the solar system gradually raises the temperature in the hot water tank.
  4. A backup energy source (electric, gas etc) ensures hot water supply when solar output is not able to fully meet demand.
House with solar power

The dedicated solar hot water heating system can be a single tank (as illustrated above) or a dedicated solar tank can provide pre-heated water to a main hot water tank.

What are the Different Types of Solar Panel Technologies?

There are two main groups of energy technologies which are used to generate electricity from sunlight globally.

Concentrated Solar Power (CSP)

CSP technologies produce electricity by focussing sunlight to produce heat and drive an engine connected to a generator. They are more commonly found in countries with year-round sunshine, which removes them from today’s agenda from a purely Irish context.

Solar Photovoltaics (Solar PV)

Given the constraints of CSP, Solar PV panels are more popular in terms of demand, affordability and reliability for Irish homeowners and businesses and as such, solar PV is best suited for use here in Ireland.

There are three main types of solar PV panels most commonly found on the Irish market; thin film PV panels, mono-crystalline, and polycrystalline PV panels.

Thin film panels

Thin film solar panels are produced via the spraying of a thin layer of semiconductor material over another surface made of either glass, plastic, or metal. They are incredibly thin (around 20 times thinner than traditional c-Si semiconductor wafers) making them flexible and lightweight.

A thin film panel may last for over ten years, which is usually less than the average crystalline panel. However, with consistent technological advances improving the durability of thin films, they could soon reach a twenty-year lifespan.

Mono-crystalline panels

More effective and efficient when compared to their counterpart thin films and polycrystalline panels. Monocrystalline modules are made of a single silicon crystal. Being the most efficient and highest-quality panels, they’re also the most expensive.

Most of the crystalline panels available in the Irish market are made of mono-crystalline and are usually made from a large number of small crystals.

Many MC panels fitted also use a new technology called PERC Technology (Passive Emitter and Rear Cell) designed to capture reflected light at the rear of the panel to improve efficiency

Peimar monocrystalline solar panels, produced using a combination of innovative production processes and advanced engineering techniques, provide Irish solar consumers with maximum output and high performance. This allows fewer panels to be used to generate more energy, ideal if space is restricted or environmental conditions are challenging.

Modern design, using matching black cells, backsheet and frames with a long lifespan make this particular monochrystalline panel option an increasingly popular choice throughout Ireland’s regional residential hubs.

Poly-crystalline solar panels

The cells on polycrystalline PV panels are formulated by melting together several fragments of silicon rather than a single silicon crystal as in the case of mono-crystalline. The differences in efficiency creates a need to use larger poly-crystalline panels that can generate the amount of energy required. Poly-crystalline are less efficient when compared to mono-crystalline and are, therefore, cheaper.  

Types of solar panel technologies

Mono, Poly and Thin Film solar panels

Ref: https://www.energysage.com/solar/101/types-solar-panels/

Matt black panels are also very popular in Ireland with both customers and city planners due to their visually more attractive profile...

Happy young family

How Long do Solar Panels last for?

Solar panels usually last somewhere between 20-30 years. This does not mean that solar panels stop generating electricity after this timeframe, but rather it means that their efficiency will substantially reduce.

This time indicates that energy production will decrease on the basis of what the manufacturer considers to be the optimal average production.

Do Solar Panels Work on Cloudy and Rainy Days?  

Perhaps the most common question we get asked in relation to solar energy in Ireland! Thankfully, modern solar panels still work properly during cloudy, wet and rainy days.

However, solar panels are naturally most efficient during sunny weather because of the direct sunlight being harnessed from the sun. In inclement weather conditions, solar panels will still generate power as the solar cells are usually powered by light and not solar heat.

US-backed research has shown that high heat may actually cause solar panels to work less efficiently. Nevertheless, today’s technology requires rigorous testing of solar panels to ensure high efficiency and effectiveness.

For solar panels to be certified for installation on an Irish home, they are usually subjected to rigorous reliability tests which include; dump heat tests, thermal cycling, and humidity freeze, among others.

Mother and young child looking out rainy window

What are the Advantages of Using Solar Power?

There are numerous advantages of using solar power. Here, we cover some of the main ones:

Solar energy is a truly renewable energy source which does not deplete on usage

This means that solar energy can be harnessed in all the areas of the globe unlike some other sources such as fossil fuels.

Solar energy will substantially reduce your electricity bills

Meeting your energy needs by your own installed solar energy system will cut on your energy bills. The amount saved by the system depends on its size or the size of heat usage in your home; the current recommendation from the SEAI is that a solar system should be sized to cover a maximum of 70% of annual electricity usage.

Home appliance energy usage per hour: Electric shower 8500w or €1.70. Tumble dryer 5000w or €1. Electric kettle 3000w or 60c. Immersion heater 3000w or 60c. Laptop 60w or 1.2c. Clothes iron 1000w or 20c.

Irish Solar installers will produce a report for your home using bespoke software that uses your location or Eircode to determine the potential output of your system. Determining factors include, location, system size, roof orientation South-facing is best but East-West orientation also works very well.

Systems from three to six kWh are most popular. Six kilowatt systems are the maximum domestic systems currently allowed in Ireland however commercial systems can be much larger but must conform to the rules set by ESB Networks

From your solar installation, there is also a likelihood of receiving payments for the surplus energy generated

This is possible when your system is connected to the company’s power grid or the national grid. Make sure to check this possibility with your installer. If you generate more electricity than you require, the extra energy is sent to the grid and you’re compensated. In case your system generates less energy than is required, the grid can also use the extra energy sent there to meet the deficit.

Feed in Tariffs (FIT) will be available from mid-2021 as per EU directive. However, the value per kWh is still unknown and the unofficial launch date for roll-out and compliance is June.

Solar energy has diverse applications throughout your home

You can generate thermal energy or electricity for application in your home. Thermal energy will be used to heat your house during the winter period. Solar energy can be used to generate electricity in areas without access to the energy grid, to distil water in areas with limited clean water supply, and to power satellites installed in space.

Solar energy has low maintenance costs

Solar energy systems have no moving parts like wind turbines, which means that wear and tear are eliminated. The inverter and the batteries are the only components that may require to be changed in about 5-10 years.

Thus, the lower maintenance cost of solar panels means lower system costs, and more savings for you in the long run.

Woman holding piggy bank

What are the Disadvantages of Solar Energy Installation?

Like anything with a list of pros, there are also some cons to consider when weighing up solar as a viable solution to your future home energy requirements.

The initial cost of installing solar panels can prove substantial

The cost includes paying for solar panels, inverter, batteries, system wiring, and the installation fee.

With market competition and new solar technologies, Irish suppliers are constantly reducing the cost of solar energy.

Solar panels may not generate enough energy during prolonged spells of poor weather

Although your solar panels still generate energy during cloudy and rainy days, they may not generate enough energy to meet your home’s specific load requirements.

Of course, any power deficit can be comfortably met with the battery stored energy or from the excess energy sent to the energy grid.

Naturally, solar panels work at their optimum during summer months and therefore les solar energy is produced during winter months. The main reason for this is solar irradiance, how long the sunshine’s (18 hours a day in summer and as little as 8 in winter months) the sun is also lower in the sky during winter months.

Graph showing solar irradiance
Graph showing solar generation Ireland
Graph showing typical day of a solar battery system

Solar panels may require a large space for installation

The more energy you need to produce, the more the solar panels will be required. This means that a standard house roof may not be enough to install all the solar panels required.

This challenge can be mitigated by having the installer assess your home or business first before installation takes place. 

House on mountain

Are there any Government Incentives for Solar Energy in Ireland?

There are several incentives in place to help Irish consumers make the switch to solar energy.

Basic requirements to qualify for solar grants include that your home must be built before 2011 and house must achieve a minimum C3 Building Energy Rating (BER) when installed.

Grants of up to €3000 are currently available and it is envisaged that they will be available in the current format until the end of 2021.

In December 2017, Department of Communications, Climate Action, and Environment (DCCAE) announced Cabinet approval for the introduction of a support scheme for Renewable Heat.

The Renewable Heat Incentive (RHI) allocated about €7 million from the 2018 budget in order to fund the initial stages of the scheme. The first allocation was successfully opened in the summer of 2018. RHI is currently exchequer-funded, and solar-thermal technology is potentially eligible for support under the respective scheme.

The 2019 budget proposed a further measure to support renewable projects, which included an estimated €500 million Climate Action Fund as well as a €500 million Disruptive Technologies Fund.

The Irish government has recognised the positive role played by solar energy as indicated by the adoption of Climate Action Plan and the identification of potential 1.5GW of grid-scale solar power in Ireland by 2030.

Our government remains committed to solar energy and it remains a long-term method of broadening the sustainable energy mix in Ireland.

Couple on the couch with kids running around

How Much will it cost for a Solar Energy System in My Home?

The cost of solar panels and the respective Solar Energy system you opt for is dependent on the amount of power you need for your home or business. The amount of power is determined by the size of the load that has to be powered by the solar energy generated.

Furthermore, the cost of solar panels and the energy system also depends on the terms offered by the company carrying out the installation. Therefore, it is important to engage the company offering installation services and get a quotation for your desired solar energy system.

In all cases, the solar installer will need to visit your home or business in order to determine the number of solar panels that may be required. They'll also be able to determine whether your roof or selected area offers enough space and is structurally fit for solar panel installation. There are many factors that go into determining the cost of solar energy.

Estimating, solar panels in Ireland usually cost between €5000 and €10,000 depending on the chosen company.

When you are charged €10,000 or more at the higher end of the scale, your energy system is above the average application for a standard family home if not a large B&B or of similar capacity.

On the other hand, when you’re charged at the lower end of the scale towards the about €4500 after SEAI Grants, your system is likely smaller without battery and of the lower standard required for a typical 3-bed semi-detached family home application.

When choosing your installer, it’s important to do your homework and be careful when evaluating the quality of the solar panels and service chosen. Lower cost might consequently mean lower quality and the solar energy system may not last for a long time.

On average, solar panels in Ireland should cost somewhere between €5000 and €7500. The cost is applicable to VAT and you may well be entitled to government incentives to help reduce overheads, once the wading body’s eligibility requirements are met.

Please see the SEAI solar grant eligibility requirements as a guide.

Woman using calculator