Time-of-use rate

A time-of-use rate is a utility tariff where the price of grid electricity depends on the time of day, so energy costs most during certain periods. Utilities are moving the expensive TOU periods later into the afternoon and evening. At those times solar output falls, peaker plants come online and the grid is under more stress. Storage systems can lower energy costs under a TOU rate by charging the battery during cheap periods and discharging it when prices are high. On some SMA systems these periods are set as schedules in the LCS-Tool. SMA advises leaving this Time of Use function off in PV-only plants, because it only works when a battery is present. TOU meters split energy and demand by rate period, labeled Rate A, Rate B and so on. Some meters also show the active TOU rate and season on the front panel. Home energy displays can colour-code the grid purchase tariff, showing red for expensive periods and green for good-value ones. This helps owners move consumption to cheaper times.

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• sentence 2: support check: partial - Passage says TOU periods shift later, the sun sets, peaker plants and grid stress rise; it does not literally say solar output falls, though the sunset implies it.
• sentence 5: support check: partial - Rate A–D periods and front-panel active TOU rate/season screens are present, and TOU metering of energy and demand is named, but splitting by rate period is only implied.
• sentence 6: support check: partial - Passage states red is expensive and green is good value for the purchase tariff, but not that this helps owners shift consumption. -->