Are You Losing Money Without Knowing?
After solar installation, most homeowners never review their energy contract. But your electricity needs have fundamentally changed: you now produce energy, consume differently, and export surplus. Your old contract is almost certainly costing you hundreds of euros per year in unnecessary charges, wrong potencia, bad tariff structure, or undervalued surplus compensation.
What Our Annual Check Covers
A comprehensive 50+ point inspection of your entire energy ecosystem, from panels on the roof to the contract on your bill.
Solar Panel Performance
- Visual inspection for micro-cracks, hot spots, and delamination
- Production vs. expected yield comparison (kWh/kWp)
- Panel cleaning, dust, pollen, salt, bird droppings
- Mounting hardware and waterproofing check
Inverter & Electronics
- Inverter error log analysis and firmware version check
- MPPT tracking efficiency measurement
- AC/DC connection tightness and cable condition
- Grounding and surge protection verification
Battery System
- State of Health (SoH) measurement, capacity degradation tracking
- Charge/discharge cycle analysis
- BMS (Battery Management System) firmware updates
- Temperature monitoring and ventilation check
Energy Contract & Tariffs
- Review of current electricity contract (comercializadora)
- Potencia contratada (contracted power) optimization, many homes overpay by 20–40%
- Tariff comparison: 2.0TD, 3.0TD, which is best for your consumption?
- Surplus compensation (excedentes) rate analysis, are you getting fair value?
Consumption Analysis
- 24-hour consumption profile, when do you use the most energy?
- Self-consumption ratio calculation (% of solar used directly)
- Grid dependency analysis, how much do you still buy?
- Recommendations to shift consumption to solar hours
EV Charger & Smart Home
- EV charger functionality test and software update
- Smart charging schedule optimization (charge with solar)
- Integration check with home energy management system
- Pool heat pump and A/C energy efficiency review
Understanding Your Energy Bill
Surplus, potencia, tariff periods, Spanish energy bills can be confusing. Here's what every solar owner needs to know.
What are 'excedentes' (surplus)?
When your solar panels produce more electricity than your home consumes, the excess is injected into the grid. This surplus energy is called 'excedentes' in Spain. Under Royal Decree 244/2019, your energy company must compensate you for this surplus on your monthly electricity bill.
How much do I earn from surplus?
Surplus compensation rates vary by provider, typically €0.05–0.10/kWh. However, this compensation can only offset your consumption charges, not fixed access fees. With a battery, you maximize self-consumption first (saving €0.15–0.25/kWh) and only export the true remainder. We analyze your specific contract to ensure you're getting the best rate.
What is 'potencia contratada'?
Potencia contratada is the maximum power (in kW) that your electricity connection can deliver simultaneously. In Spain, you pay a fixed monthly fee for this capacity, regardless of whether you use it. Most homes have 2 potencia levels (peak and off-peak). After installing solar + battery, many homeowners can safely reduce their potencia by 1–3 kW, saving €100–300/year on fixed charges alone.
What tariff structure is best for solar owners?
Spain uses time-of-use tariffs with 3 periods: Punta (peak, 10–14h & 18–22h), Llano (flat, 8–10h & 14–18h & 22–24h), and Valle (off-peak, 0–8h). For solar owners, the key is to shift consumption to Llano/Valle hours and use solar during Punta hours. With a battery, you can virtually eliminate Punta consumption. We compare rates across 15+ comercializadoras to find the optimal contract.
Can you switch my energy provider for me?
Yes! With our Professional and Premium plans, we handle the entire process. We analyze your consumption, compare providers, recommend the best option, and manage the switch. There's no interruption to your electricity supply. The process typically takes 2–3 weeks and can save you €200–600/year.
Energy Advice for Your Solar Installation
Installing solar changes how you consume and produce energy. Your electricity contract should reflect that, surplus compensation (excedentes), the right tariff structure, and a retailer that fits a self-consumption setup. As your energy advisor (asesor energético) we help you move to a suitable contract after installation, without acting as an independent tariff comparator or referral service.
Asesor energético: what we do
We review your bill, contracted power (potencia), surplus rate and self-consumption ratio, and advise whether your current contract still makes sense, or which type of contract fits a home that now produces energy.
Cambiar de compañía de luz after solar
Switching retailer isn't mandatory, but a self-consumption-friendly contract with fair surplus compensation often saves €200–600/year. Where it makes sense we manage the entire switch, no supply interruption.
Which contract type fits you
Fixed, variable or feed-in tariff with surplus compensation: the best fit depends on when you consume, whether you have a battery, and how much surplus you export. We advise on the right structure for your self-consumption installation, not a generic cheapest-tariff list.
Do I need to switch electricity company when I install solar panels?
You don't have to, but it often pays off. Your old contract was taken out before you produced energy, so it rarely rewards your surplus (excedentes) fairly or matches your new self-consumption pattern. After installation we review whether switching to a retailer with better surplus compensation or a self-consumption-friendly tariff makes sense, and handle the switch where it does, with no interruption to your supply.
What is an asesor energético and when do I need one?
An asesor energético reviews your electricity bill, contracted power (potencia), surplus rate and consumption profile, and advises whether your contract still makes sense now that you produce energy. We act as your energy advisor alongside the installation, not as an independent tariff comparator that refers you to multiple retailers. You benefit most from this advice right after installing solar or a battery, when your consumption pattern has fundamentally changed.
Which electricity contract type fits a self-consumption solar installation?
It depends on when you consume, whether you have a battery, and how much surplus you export. A fixed tariff gives predictability; a variable tariff can suit homes that shift consumption to solar hours; a feed-in tariff with surplus compensation (excedentes) matters once you regularly export. We advise on the right structure for your installation, not a generic 'cheapest tariff' list.
What is a gestor energético and is it included?
A gestor energético actively manages your energy contract over time, adjusting contracted power, switching tariffs when better terms appear, and keeping surplus compensation competitive as the market moves. It is part of our Professional and Premium annual check plans, so your contract keeps working for you long after the panels are on the roof.
Related: solar subsidies and IRPF deductions in Andalusia. See subsidies & IRPF
Typical Annual Savings Breakdown
* Savings vary depending on system size, consumption pattern, and current contract. Based on real client data from 2025–2026.
Major Energy Suppliers We Work With
We can compare, optimize, and manage switches across all major Spanish energy brands. These are 10 of the biggest suppliers we review most often for solar homes on the Costa del Sol.
Iberdrola
One of Spain's largest electricity suppliers.
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Endesa
Major national supplier for homes and businesses.
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Naturgy
Large energy group with broad tariff options.
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Repsol
Strong retail energy brand with solar-focused offers.
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TotalEnergies
International provider active in the Spanish market.
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EDP
Well-known Iberian provider with residential plans.
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Holaluz
Popular renewable-focused supplier in Spain.
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Octopus Energy
Fast-growing provider with smart tariff positioning.
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Acciona Energía
Spanish renewable energy leader with retail presence.
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Plenitude
Growing Spanish-market supplier for home contracts.
Visit supplierAnnual Check Plans
Choose the level of service that matches your energy setup. All plans include at least one on-site visit per year.
Essential
Perfect for small residential solar systems up to 5 kWp.
- Annual on-site inspection & cleaning
- Energy contract review & optimization
- Surplus (excedentes) analysis
- Potencia (contracted power) check
- Digital performance report
- Phone & email support
Professional
Comprehensive coverage for solar + battery systems up to 12 kWp.
- Everything in Essential, plus:
- Battery health check & firmware updates
- Inverter diagnostics & optimization
- Tariff comparison across 15+ providers
- Consumption pattern analysis (24h profile)
- Self-consumption optimization report
- Priority support, 24h response
Premium Villa
Full-service for large villas with solar + battery + EV + pool systems.
- Everything in Professional, plus:
- 2x annual visits (spring + autumn)
- EV charger inspection & software updates
- Pool heat pump energy audit
- Potencia & tariff switch execution (we handle everything)
- Emergency call-out, 4h response
- Annual energy savings guarantee
How the Annual Check Works
We Schedule
We contact you to schedule a convenient date for the on-site visit.
On-Site Inspection
Our engineer inspects your entire energy system, panels, inverter, battery, wiring.
Contract Analysis
We analyze your electricity bills, tariffs, potencia, and surplus compensation.
Action Report
You receive a detailed report with concrete recommendations and projected savings.
Request Your Free Energy Audit
Tell us about your solar system and we'll analyze your potential savings, completely free, no obligation.
Get Your Free Solar & Battery Proposal
Official Sources & Partners
External links to official sources and partners. MiTechoSolar.com is a brand of Mi Techo Solar.