Energy balance means adding up the power flows at the grid-connection point (PV production, grid feed-in and grid draw) to work out how much energy the site's loads actually consume. When PV is connected on the load side of the meter, consumption is PV production minus feed-in. For example, 50kW produced with 40kW fed in gives 10kW of load. To make this work, a measurement source such as an energy meter must be fitted at the grid-connection point, positioned so that household loads can use PV energy before it reaches the feed-in point. If PV is wired on the grid side of the meter, the calculation adds PV on top of grid draw and overstates consumption. Monitoring then shows production mirroring consumption. Feed-in that appears at night usually means the meter, a CT or a current-measurement lead is installed the wrong way round. Check CT orientation, CT ratio, and that grid power changes when you switch the inverter on and off. Three-phase meters can add up import and export phase by phase, or by the direction of total power for billing. The two methods give different import and export totals for the same period.
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related_toc1 verified · fact Energy meter
A measurement source such as an energy meter has to be present at the grid-connection point. Meter placement decides whether the balance comes out right.
sec=h217 h=caf6c20f13c6sec=h1 h=671005070a40sec=h36 h=335e0ec8708dverified by: review-workflowverified on: 2026-10-24
c2 drafted · lead Point of interconnection
The balance uses drawn power, fed-in power and reactive power measured at the point of interconnection.
tbl=38 h=173265fd66detbl=10 h=b44bc0da7931sec=h501 h=bc1116db50bfreview note: support check: partial - Passages list drawn, fed-in and reactive power at the grid connection point, but do not describe an 'energy balance' using them.
c5 verified · fact Energy meter installation position error
sec=h1 h=671005070a40verified by: review-workflowverified on: 2026-10-24
c6 verified · fact Self-consumption optimization
Power control at the grid-connection point tries to use PV energy on site, or store it, before feeding it in, and to supply loads from PV or the battery before drawing from the grid.
verified by: review-workflowverified on: 2026-10-24
c7 verified · fact Export limitation
Limited Export works with a meter at the grid-connection point. Inverter output rises or falls by the amount of self-consumption.
sec=5.2.7 h=05e66d8a958bverified by: review-workflowverified on: 2026-10-24
c8 drafted · lead Zero export
sec=h75 h=3946a1e40165c9 drafted · lead Self-consumption rate
tbl=41.r1 h=4187ba7a2f23review note: support check: partial - Self-consumption rate is defined as ratio to total yield, but no link to grid-connection energy balance is stated.
c10 drafted · lead Self-sufficiency rate
tbl=41.r1 h=4187ba7a2f23review note: support check: partial - Self-sufficiency quota is defined, but no relation to the grid-connection energy balance is stated.; review: partial - The table defines the self-sufficiency quota next to grid feed-in and self-consumption totals, but it never ties the metric to the energy balance at the grid-connection point.
c11 drafted · lead Consumption metering proposed
review note: support check: partial - Passages mention current consumption and an Energy Balance page, but not consumption metering at the grid connection point.
explainsc3 drafted · lead Generation equals consumption reading proposed
If PV is connected on the grid side of the meter, the meter only ever sees power drawn. The calculated consumption then follows PV production.
sec=h1 h=671005070a40c4 drafted · lead Grid feed-in at night proposed
If the meter, a CT or a current-measurement lead is installed the wrong way round, the sign of grid power flips, so the system shows feed-in at night.
sec=h1 h=671005070a40review note: support check: partial - Incorrect orientation of meter, CT or leads is given as possible reasons for night feed-in, but the 'sign flips' mechanism isn't explicitly stated.