Author
Adam Millington is the founder and co-owner of Marblanc Solar. He is a fully qualified electrician with a QQI Level 6 Advanced Certificate Craft –Electrical and a Masters in Sustainable Electrical Energy Systems at the Technological University Dublin.
Wondering how much solar panels can save you in Spain?
You’ve found the right post.
Below, you’ll find 5 case studies from Marblanc Solar clients, including before-and-after electricity bill comparisons from solar installations in Spain. You’ll learn to calculate savings based on electricity costs – and ignore unavoidable standing charges and taxes.
You’ll also see:
- How large luxury villas can hit break-even within 6 months
- Proof that €0 electricity costs are possible in Spain
- How to design a system for 100% savings
- The #1 limiting factor
- Why some homeowners go solar even without any savings
Let’s get into it.
Get a Free Solar Survey Worth €159
Want an in-depth solar proposal tailored to your property?
It will cost you at least €159 to hire a survey engineer, scan your property with a drone, and pay for the best solar design software (Pylon).
Click below to have Marblanc Solar do it all for free in 1-3 working days.
Free Solar Survey€2,878 Monthly Saving – Luxury Villa On Track for 6-month Break-Even
Location: Nueva Andalucía, Marbella
System size: 22kW (39 panels)
Expected saving: 80% cost reduction
This 22 kW solar installation in Marbella by Marblanc Solar reduced the homeowner’s electricity bill from €3,310 to €432.
That’s a €2,878 saving.
The pre-solar bill (see below) was from July 2024 while the post-solar bill was from March 2025. So it’s not the full picture.
In summer months, we expect the homeowner’s post-solar bill to be a 80% reduction down to ~€700/month, reflecting seasonal demand from heat pumps, pool heating, and a high-usage villa lifestyle.
Not every home in Spain has a bill this high.
But this remarkable result is strong proof of the value of solar panels for luxury villas in Spain – even without a solar battery. In this case, the homeowner is on track to break even in 6 months.
€182 Monthly Saving – Villa Cuts Electricity Cost to €0 Thanks to “Virtual Battery”
Location: Manilva, Costa del Sol
System size: 11.9kW (20 panels)
Expected saving: 87% cost reduction
This 11.9 kW solar installation in Manilva by Marblanc Solar reduced the homeowner’s electricity costs from €182 to €0.
That’s a €182 saving.
The pre-solar bill (see below) was from October 2024 while the post-solar bill was from October 2025. But the final costs don’t tell the whole story.
In October 2024, the client was charged €182.62 but received an unrelated discount, which cut the final cost to €167.57. The October 2025 bill shows the client was charged €0 for electricity costs and even earned €9.44 in their virtual battery.
But the €40.04 final cost is due to standing charges and taxes.
This result highlights 3 key aspects of solar panel savings in Spain:
- How to calculate savings – It’s better to calculate savings on electricity costs, rather than final bill costs. This is because standing charges, taxes and discounts blur the picture.
- Get a virtual battery – Without a virtual battery, we calculated the client would have paid €50.82 extra in this bill.
- Compare providers – We help clients compare virtual battery providers to find a deal with the lowest standing charges.
€148 Monthly Saving – Villa With Electric Car Charger Eliminates Electricity Costs
Location: Fuengirola, Costa del Sol
System size: 10.1kW (17 panels)
Expected saving: 100% cost reduction
This 10.1 kW solar installation in Fuengirola by Marblanc Solar is designed to cut the homeowner’s electricity costs from €148 to €0.
We predict they’ll even save €19 a month in virtual battery credit.
The savings are based purely on electricity costs – and don’t include standing charges and taxes.
As part of our Free Solar Survey, we used a drone to scan the client’s roof and then plugged the results into Pylon solar design software. We then calculated the solar panels necessary to sell more to the grid than they bought, based on current consumption patterns.
This design was important as we installed a 7.4kW EV charger.
The client should be able to charge their electric car while keeping electricity costs at €0 – even without having a solar battery.
€152 Monthly Saving – Homeowner Sees Lower 53% Savings due to Aesthetic Requests
Location: Marbella, Costa del Sol
System size: 6.9kW (16 panels)
Expected saving: 53% cost reduction
This 6.9 kW solar installation in Marbella by Marblanc Solar is designed to cut the homeowner’s electricity costs from €328 to €153.
(Predicted savings do not include standing charges and taxes.)
The 53% reduction is short of the 80% we usually aim for. But the client made two requests during our Free Solar Survey at the property:
- All-black panels – The client asked for “all-black” solar panels, which have better aesthetics but a lower output. In this case, we installed 430W JA Solar DeepBlue 4.0 Pro panels instead of our usual 595W or 615W.
- Restricted space – The client requested that the solar panels be installed on the upper roof section. This limited the system’s savings potential.
This case study is important to recognise that clients often value aethetics over maximising how much the solar panels will save.
€0 Monthly Saving – But Homeowner Charges EV for “Free” with Solar Financing
Location: Mijas, Costa del Sol
System size: 6.4kW (11 panels)
Expected saving: 83% bill reduction
This 6.5 kW solar installation in Mijas by Marblanc Solar was designed to reduce the homeowner’s electricity costs from €152 to €26.
That’s a €126 saving.
But as the homeowner financed their installation, we calculated the former electricity bill is roughly the same as the new bill plus financing repayment.
Let’s run the maths.
In June 2025, the client received a bill for €229 – that’s €152 in electricity plus charges and taxes. Our Free Solar Survey proposal predicted their electricity costs post-solar will average €26.
When you add together:
- €26 average electricity costs
- €30-40 in charges and taxes
- €153 financing repayment
The resulting figure is around the €229 total they paid pre-solar. Except that, now they have a home solar energy system, an electric car charger, and are paying off their investment – rather than giving money to Endesa.
This case study shows that solar panels aren’t always about immediate savings.
Get a Free Solar Survey Worth €159
Want an in-depth solar proposal tailored to your property?
It will cost you at least €159 to hire a survey engineer, scan your property with a drone, and pay for the best solar design software (Pylon).
Click below to have Marblanc Solar do it all for free in 1-3 working days.
Free Solar Survey