Frequently asked questions

To launch our service in November 2026, the first 99 evaluations are free and need no sign-up. After that, the detailed report with the suitable providers and tariffs costs 15 €; this is how we fund the service.

No. The calculator reads the PDF in memory only and does not store it. This website itself sets no cookies and uses no tracking.

They are estimates, not advice and not guaranteed. Your contract and the official sources (CNMC, BOE, REE) prevail. Where the calculator makes assumptions, it shows them.

We show which tariffs are cheapest for you. They are based on the household offers in the official electricity comparison of the Spanish regulator (CNMC), calculated with your figures.

No. Solemo's Swiss offer is separate and unrelated to this website.

Energy: P1 (peak) Mon–Fri 10–14 and 18–22 h, P2 (flat) 8–10, 14–18, 22–24 h, P3 (valley) 0–8 h. Saturday, Sunday, 6 January and fixed-date national holidays are P3 all day (2026: 1 Jan, 6 Jan, 1 May, 15 Aug, 12 Oct, 1 Nov, 6 Dec, 8 Dec, 25 Dec). Not P3: Good Friday, regional/local holidays and Monday substitute days (e.g. 2 Nov and 7 Dec 2026). Power: P1 Mon–Fri 8–24 h, P2 the rest.

Sources: boe.es · boe.es

Regulated parts of every bill, identical for all suppliers. Power (EUR/kW yr): P1 23.324952 + 4.379461, P2 0.443770 + 0.281653. Energy (EUR/kWh): P1 0.033261 + 0.064292, P2 0.016409 + 0.012858, P3 0.000077 + 0.003215 (toll + charge).

Sources: miteco.gob.es · boe.es · boe.es

Hourly price, only from reference suppliers, only up to 10 kW. Since 2026 the energy price is 55 % forward market (month 10 %, quarter 36 %, year 54 %) and 45 % day-ahead/intraday (RD 446/2023). Fixed retail margin EUR 3.113004/kW yr (Orden ETU/1948/2016). Bono social is only available with PVPC.

Sources: boe.es · boe.es · esios.ree.es

5.11269632 % on power + energy, at least EUR 1/MWh (households). 2026: 0.5 % from 22 Mar to 31 May (RDL 7/2026); June to November standard rate; December 0.5 % only if October electricity CPI meets the RDL 25/2026 threshold (open). Energy offset by compensation in the same month is exempt.

Sources: sede.agenciatributaria.gob.es · sede.agenciatributaria.gob.es

Standard 21 % on everything incl. IEE and meter rental. Until 31 May 2026 10 % applied (RDL 7/2026). For Nov/Dec 2026 RDL 25/2026 provides 10 % for up to 10 kW and bono social customers, only if electricity CPI in Sep/Oct is more than 15 points above the prior year. Not met for November (21 %), December open. The app uses 21 %.

Sources: sede.agenciatributaria.gob.es

Smart meter single-phase EUR 0.81/month, three-phase EUR 1.15/month plus VAT; the meter can also be purchased.

Sources: consumoresponde.es

Discount for recognised vulnerable households, PVPC only: 42.5 % (vulnerable) / 57.5 % (severe) until 31 Dec 2026, then 35 % / 50 %. Applies fully to power, to energy up to an annual limit. The 'bono social financing' line on free-market bills is a small cost paid by all customers.

Sources: miteco.gob.es · miteco.gob.es

Free, no new meter, max. 10 working days (up to 15 with field work). Households can cancel at any time; a penalty is only possible on fixed-price contracts before the first renewal (max. 5 % of the pending energy). The new supplier handles the switch (RD 88/2026).

Sources: miteco.gob.es · cnmc.es

1) Without surplus: no export. 2) With surplus under compensation: renewable, up to 100 kW, surplus offset monthly against the energy term. 3) With surplus not under compensation: sale on the market, a generation activity for tax purposes. Collective: generation in the same building/network < 500 m or PV/wind up to 5 MW via the grid up to 5,000 m (since RDL 7/2026, previously 2 km), measured between meters.

Sources: boe.es · miteco.gob.es · iberley.es

Per billing period (max. 1 month): value of grid energy minus value of surplus, result at least EUR 0. Only the energy term falls; power, meter rental, bono social financing remain. IEE and VAT are then applied to the smaller base. Surplus price: with PVPC the hourly market price minus imbalance costs (often 2–6 cents), on the free market the agreed price (often 4–6 cents excl. tax). Anything not offset is lost unless you have a virtual battery.

Sources: boe.es · libreria.miteco.gob.es · iberley.es

Not a law but a supplier product: the non-offsettable remainder is stored as euro credit and later deducted from the bill total (also power and taxes, depending on supplier also gas or other supply points). For tax purposes credit from earlier months does not reduce the tax base (DGT V1146-24); it is only a means of payment. Examples (as of 1 Nov 2026): Naturgy EUR 0/month, EUR 0.06/kWh (revisable monthly), credit valid 5 years, usable for all Naturgy bills of the same holder incl. other supply points; Endesa EUR 2/month, EUR 0.06/kWh, same supply point; Repsol EUR 1.99/month, EUR 0.06/kWh. Note: a higher energy price on the solar tariff can eat up the advantage.

Sources: naturgy.es · naturgy.es · endesa.com · repsol.es · cuatrecasas.com

1) Municipality: declaracion responsable or licence (see below). 2) The authorised installer registers the system in the Junta's PUES portal: up to 10 kW technical report + installation certificate (CIE), above that a project. 3) Entry in the self-consumption register is ex officio (LV < 100 kW). 4) Distributor (usually e-distribucion): without surplus up to 15 kW no grid connection request; a CAU is assigned. 5) For compensation: contract via your supplier. Without these steps there is no compensation and no tax benefit.

Sources: juntadeandalucia.es · edistribucion.com

Seville: rooftop PV outside the historic centre by declaracion responsable with a technician; protected buildings need a licence. Malaga: renewable self-consumption up to 500 kW by declaracion responsable. Other municipalities: check the local ordinance.

Sources: urbanismosevilla.org · malaga.eu

ITC-BT-40 (low-voltage regulation REBT): requirements for generation systems on the LV grid (protection, disconnection, earthing, connection to the house installation). ITC-BT-52: EV charging infrastructure (dedicated circuit, installation schemes, protection devices); every wallbox needs an installation certificate. CTE HE5 requires minimum generation for new builds/major works (residential from 1,000 m²); a normal single house is not obliged. CTE HE6 requires charging pre-installation in new buildings with parking.

Sources: boe.es · boe.es · codigotecnico.org