Dynamic electricity tariff

A dynamic electricity tariff is an energy contract in which the price changes every hour or every quarter hour instead of staying fixed. Prices often come from the day-ahead market, such as the EPEX price. The next day's rates are loaded automatically into the energy management system. The raw market price can be adjusted with a coefficient or a fixed amount to cover extra costs such as transport charges or VAT. Purchase and feed-in rates can each have their own offset. With a battery, the system can charge from the grid when prices are low or negative and discharge or export when prices are high. This is the basis of energy arbitrage. When prices turn negative, the inverter can limit export to zero or shut PV down completely to avoid extra costs. This means a planned power limit is not necessarily a fault. Some revenue meters have a real-time pricing mode. While a control signal or input is active, the meter keeps a second, separate set of energy and demand totals. Home energy managers also use the tariff data you enter to plan load control and recommended actions. Related concepts include time-of-use rates, feed-in tariffs and self-consumption.

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• sentence 1: support check: partial - Passage says dynamic contract prices change every hour/quarter, but does not explicitly contrast with fixed prices (though fixed rate is mentioned separately).
• sentence 4: support check: partial - Charging at low/negative prices and discharging/exporting at high prices is stated, but the passage does not call it the basis of energy arbitrage (only names the Peak-Valley Arbitrage mode).
• sentence 5: support check: partial - Limiting export or shutting PV down under negative prices to avoid costs is stated, but the claim that a planned limit is not a fault is not stated.
• sentence 7: support check: partial - Tariff values affect recommended actions and load control, but time-of-use rates and feed-in tariff/self-consumption as related concepts are only loosely supported (feed-in and self-consumption tariffs appear; TOU not).
• sentence 7: review: partial - SMA says the tariff values entered drive recommended actions and Sunny Home Manager load control, and feed-in and self-consumption tariffs appear, but time-of-use rates as a related concept are not in the passages. -->