Save money by switching your home energy to solar power
I went into January €261 in credit with my electricity supplier, Electric Ireland (EI). This is not smug bragging, I’m advocating. To run an EV car and the entire house in 2022, this was a rare win, and hardly terrifying, looking ahead to 2023/2024.
We owe this bounce to the considered use of our solar-photovoltaic panels, utilising the potential of a 6.5kWh storage battery, and being disciplined around the proven advantages of time-of-use energy tariffs (T-o-U). I enjoy a steady, seasonal performance from a relatively small 4.2kWp PV-solar system c.2019, and it’s something that every family in Ireland should be assisted in adding to their domestic energy round.
All I see are useless, bald roofs bathed in sunshine all over the country as we hunker down in this energy crisis. I get asked about solar-PV every week by readers, so here are a few answers for newbies, considering renewable technology in 2023.
For fuller information log on to the Sustainable Energy Authority of Ireland’s website and explore their excellent Home Energy pages. Then join the Irish Solar PV & Battery System Owners Group on Facebook, which boasts over 37,000 members.
You don’t need to be an owner to join, in fact, it’s an excellent place to ask all those perplexing questions of both suppliers and PV-solar users, some of whom have self-installed their systems forgoing SEAI grant aid (commissioning with a RECI-certified electrician, of course).
Some 46,500 people have taken the step to domestic solar so far in Ireland. "Rising energy prices and climate concerns have turbocharged customer interest in rooftop solar panels," says Conall Bolger, CEO of the Irish Solar Energy Association (ISEA).
Being present at home by day, you can be reactive to solar-PV energy collection as it happens. This has made PV extremely popular with retirees.
There’s a hobbyist excitement to squeezing the best from every lingering kWh off the roof.
Being present at the house, excess power can go into a battery, water heater, PHEV or BEV. In winter you can enjoy the gain contributing modestly to running a heat pump, or other electrical heating such as infra-red panels.
That said, with battery collection and the Micro-generation Support Scheme (MSS), even when you’re not there, your solar-PV system can be working to reduce your bill.
Once living in the light, you will start out with an anxious eyeball trained on the software read-outs day long. Most solar-PV householders eventually stop obsessing with scudding clouds and energy spikes, and just let the system passively do its thing.
In my opinion, engaging as fully as possible with the benefits of solar-PV radically alters the bottom line. Depending on the weather, I might run several loads of laundry in a single sunny day (with machines running sequentially where possible). I’ll still see excess power going back to the national grid to be repaid via the MSS.
During the same time, a trace of kWs continues to heat my water through the water diverter, and my battery is taking in enough kWhs to get me through the evening (4kWh is plenty). My ideal is to be using my PV for my household power for most, if not all, of the day for nine months of the year, except the minute amount of grid power necessary to cycle the battery.
In winter, on even a dark day, my lighting, TV and laptop are all off-grid, even if the battery lies relatively idle.
The decision on whether a battery warrants the additional up-front cost is very dependent on the customer’s budget, the scale of the solar system, the suitability of their home, and their electricity demand, according to Conall Bolger.
"A good installer can work through your options. However, it is not mandatory. Many customers get value from solar panels alone, through bill savings and payments under the MSS. We always recommend that customers get a number of quotes from suitably qualified installers, and you can find providers on the members' page of our website (irishsolareenergy.org).”
To even approach 24 hours off-grid from the second week of February in my case (a misnomer, as in Ireland, even with the biggest array, you are generally grid-tied) — you must have a battery. The cost of batteries has soared, and their inclusion can double a quote for a solar-PV system. Still, their versatility is legendary.
I cannot imagine life without being able to seamlessly segue in and out of a stored supply. Working off the battery saves on pricey peak-hour tariffs of 50c/kWh or more and allows you to reach cheaper T-o-U prices of 20c or less after 11pm. When the battery is exhausted (at 10% charge it will stop drawing down), there’s also the ability to download power at night from the grid with cheap night-time T-o-U tariffs.
This is all easily set up on the fascia touch-screen or using the software app with any solar-PV inverter. That said, with the MSS, excess power from your array can still raise at least 21c per kWh (depending on your supplier) credited back to your bill.
There is a limit to the power your system can “drop” from a battery or inverter at any one time, and there are a few high-input appliances that will always prove a challenge, blowing through your real-time gain and your battery’s stored power.
Electric power showers can demand 9kWh. A 15-minute shower could take a large bite out of any stored power in the battery and will never run completely off a medium-sized array of say 5kWp.
Boiling the kettle — you can expect to see that real-time use peak and reach out to the grid for a 2kWh to 3kWh for a few minutes at least. This reality has made me a more conservative and careful consumer — raising my awareness and changing my energy behaviours almost entirely.
If the electric shower ran for longer than five minutes, there would be a Kya-shaped hole in the bathroom door.
There’s no need to have a smart meter for solar PV or the MSS scheme. Smart meter deals are not proving to offer the best time-of-use tariffs at present, and you can benefit from T-o-U tariffs with a Day/Night meter.
The MSS pays users for excess power returned to the grid in two ways — both appearing as a kWh credit on your bill from the supplier. There’s an accurate payment for smart meter customers and a deemed-usage payment for those with 24-hour and Day/Night meters.
The deemed usage is based on an equation of presumed return based on the size and aspect of your array as set out by the Commission for Energy Regulation (CRU). Pour all of your excess power into a domestic battery or stick it in the EV? The same deemed usage is still calculated and paid out as credit.
With growing demand how long will a customer have to wait for a system to be installed?
According to ESB Networks (ESBN), in the first 11 months of 2022, 16,946 systems were installed. We’re expecting a further increase in 2023 considering the tariff for selling power back to the grid (MSS) and the removal of planning restrictions for domestic arrays, only took effect in Q4 of 2022," says Conall Bolger.
There are increased waiting times for solar-PV installations, so if you are considering getting on board, now is the time to set up an on-site survey and find out what system would suit you, the potential cost and a timeline for its installation.
Obviously, getting your array in before the high days of summer will give you an impressive result from the first relatively bright day, potentially banking some kWhs in the MSS which can take a nice nibble out of the obligatory standing charges.
For solar-PV grant aid from the SEAI, capped at €2,400, €900 per kWp up to 2kWp (of array on the roof), there is €300 for every additional kWp up to 4kWp. It can be rolled into a deep retrofit one-stop shop grant-aided deep retrofit.
- For more information go to seai.ie