What role does energy purchasing play?
The operator's energy contract runs out at year end. Three offers lie on the table: fixed for two years, indexed to the market, or dynamic by the quarter hour.
Every cent per kWh changes the business case.
The questionHow should an operator buy the electricity it sells?
| Price risk | Suits | |
|---|---|---|
| Fixed priceset for a period | with the supplier | stable prices to drivers |
| Indexedfollows a market index | shared | medium flexibility |
| Dynamicby the quarter hour | with the operator | sites that can shift load |
Many operators combine forms, for example a fixed base with a dynamic share.
Why it matters so much
Energy, with and levies, is paid for every kWh sold, so it is the largest variable cost. A fixed price protects the operator from spikes but gives up cheaper hours; a dynamic price rewards sites that can move load, for example with a battery or with slower charging at quiet times. Dynamic contracts follow market prices; EU law gives customers with a smart meter the right to one.
Flexibility as income
A site that can shift load can also sell that ability. RED III asks Member States to let small and mobile systems take part in flexibility and balancing markets, also through . For charging sites with batteries, this can add revenue, as shown in Battery storage, stop 06.
Check your understanding
3 questions. Answer all of them to complete this stop. Each answer explains itself.
Who carries the price risk in a dynamic energy contract?
Dynamic prices pass market movements to the buyer; with a fixed price, the supplier carries the risk.
Why is energy purchasing so important for an operator?
Every kWh sold has to be bought first, with grid fees and levies on top.
Which sites gain most from dynamic prices?
Only sites that can move their demand into cheaper hours benefit from changing prices.
- Aggregator A company that pools many small devices, such as cars and home batteries, so they can take part in electricity markets. Energy and grid integration, stop 02 Glossary
- Grid fee What a grid operator charges for the use of its grid; it is part of the electricity price and, for larger connections, often also depends on the highest power drawn. Stop 01 Glossary
- EUR-Lex: Directive (EU) 2019/944, Article 11: dynamic electricity price contracts. https://eur-lex.europa.eu/eli/dir/2019/944/oj. Checked 09 Oct 2026. © European Union, reused under Commission Decision 2011/833/EU.
- EUR-Lex: Directive (EU) 2023/2413 (RED III), Article 20a(5). https://eur-lex.europa.eu/eli/dir/2023/2413/oj. Checked 09 Oct 2026. © European Union, reused under Commission Decision 2011/833/EU.