Industrial self-consumption is the energy model in which a company generates part of the electricity it uses, typically with rooftop or canopy photovoltaic panels, to cover its own demand, cut its power bill and reduce exposure to electricity-market volatility. The plant stays connected to the grid and imports whatever the panels do not cover.
How industrial self-consumption works
The installation generates electricity on site and feeds it into the factory’s internal grid: solar output is consumed on the spot by plant loads, and only the difference is imported from the grid. The plant keeps buying whatever the panels do not cover, at night, on cloudy days or during demand peaks.
Modalities: with and without export
In Spain, the regulatory framework (RD 244/2019) sets out two main modalities:
- Without export. An anti-backfeed system prevents the installation from injecting energy into the grid. It is the simplest to permit, but any output the plant does not absorb at that moment is lost.
- With export. Unconsumed energy is fed into the grid. It can use simplified compensation on the bill, designed for small installations and with power limits that leave out many industrial ones, or be sold as energy on the market, directly or through a representative.
In both cases an exported kilowatt hour is worth less than a self-consumed one: compensation only offsets the energy term and is capped monthly. The modality cushions unavoidable mismatches (weekends, August, low-production days) but should not carry the business case.
How it is sized: the load curve decides, not the roof
Correct sizing starts from the plant’s real hourly or quarter-hourly load curve covering at least twelve months. Any supply with a smart meter has that data available through the distribution company. That series answers three questions: the base load that never drops, the typical load in the middle of the day, and how both vary across seasons and between working days and holidays. The solar production curve is then laid over the demand curve to measure how much energy coincides.
The roof is a constraint, not a criterion. An installation sized by available square metres usually produces more than the factory can absorb in real time, and a growing share of its output is paid at export prices. The tell-tale indicator is the self-consumption ratio: the lower it is, the more the installation was designed for the roof rather than the plant. In industry it is usually better to fall slightly short than to overshoot, leaving the installation ready to expand or add storage if the profile changes. The full method is in the guide to industrial self-consumption and sizing.
Monitoring: measuring generation and consumption together
Value grows when the installation is integrated with operations. Monitoring generation and consumption in the same time series makes it possible to check the real self-consumption ratio against the study, spot production drops and shift flexible loads into solar hours. Without that measurement savings are estimated; with it they are checked month by month.
Permitting and grants
Permitting depends on the modality and the power: an installation without export is the simplest, while a grid-exporting connection requires more steps with the distribution company and the authorities. In the Valencian Community, IVACE publishes annual energy grant calls that include photovoltaic self-consumption. Percentages, caps and deadlines are set by each call and change from year to year, and in many lines the works cannot have started before the application. How to fit the grant to the project is covered in IVACE grants for industrial self-consumption.
Why it matters for industrial SMEs
For an SME with daytime consumption and a large, well-oriented roof, self-consumption lowers cost per kWh and stabilises a historically volatile expense. It also cuts scope-2 emissions and can satisfy customers auditing their supply chain’s carbon footprint.
Related terms
Self-consumption is one lever within energy efficiency and industrial decarbonisation. It combines with BESS storage, peak shaving and a corporate PPA when the roof cannot cover the target consumption.