Smart Export Guarantee (SEG): A Complete Guide for UK Solar Businesses

The Smart Export Guarantee (SEG) replaced the Feed-in Tariff in January 2020 and remains the primary mechanism for UK businesses to earn money from surplus solar generation. Unlike its predecessor, the SEG is not a government subsidy. It is a market-based obligation on licensed electricity suppliers with more than 150,000 customers to offer a tariff for exported electricity.

For commercial solar owners, this means any electricity generated but not consumed on-site can be exported to the grid and paid for. The rates vary significantly between suppliers. As of 2025, the best SEG tariffs offer between 15p and 20p per kWh, while some legacy suppliers pay as little as 1p per kWh. For a business exporting 10,000 kWh per year, the difference between a good and poor tariff is £1,500 annually. This makes supplier selection a genuine financial decision.

To qualify for SEG payments, your installation must be MCS certified or equivalent, have a total capacity of no more than 5MW, and include an export meter. Most modern commercial inverters come with export monitoring as standard, but a dedicated half-hourly meter is required for systems above certain thresholds. Your installer should handle the MCS certification and meter application as part of the project.

Maximising export income requires more than choosing the right tariff. The timing of your export matters. Businesses with battery storage systems can store surplus morning generation and export it during peak demand periods when rates are highest. Smart inverters with export limiting capabilities also allow you to fine-tune exactly how much you send to the grid versus consuming on-site.

A frequently overlooked aspect is the interaction between SEG and your import tariff. Businesses on time-of-use contracts may find it advantageous to export during peak periods and import during off-peak periods, effectively using the grid as a virtual battery. This strategy, known as energy arbitrage, can significantly improve the overall economics of your solar installation.

The application process is straightforward. Once your system is commissioned and MCS certified, you apply directly to your chosen SEG licensee. Most suppliers now offer online portals with monthly payment cycles. At Bee Solar, we provide a complimentary SEG advisory service, helping our clients compare tariffs and optimise their export strategy based on actual generation and consumption patterns.