Define both the command and the stored energy
A dispatch schedule is a request. The battery can only follow it if power limits, remaining stored energy and site conditions permit. A 1 MW inverter does not guarantee 1 MWh in the next hour if the battery is nearly empty.
Use a synthetic example with 1,000 kW rated power, 2,000 kWh nominal energy, 50% initial SOC, 10% minimum SOC, 90% maximum SOC and 88% round-trip efficiency. Request one hour at full discharge in grid-export mode.
Follow the SOC limit
The lab splits round-trip efficiency symmetrically: charge and discharge efficiency each equal √0.88 = 0.938083. Initial stored energy is 1,000 kWh; minimum stored energy is 200 kWh. Only 800 kWh DC can leave the battery.
800 × 0.938083 = 750.47 kWh AC. Over a one-hour interval, the feasible average discharge is 750.47 kW. The schedule is clipped below its 1,000 kW request and ends at 10% SOC.
With finer intervals, the tool can represent full output for earlier intervals and a partially clipped final interval. A one-hour row is an interval average, not a guarantee of flat power every second.
Check the complete cycle
To restore the 800 kWh removed from storage, AC charging energy is 800 ÷ 0.938083 = 852.80 kWh. The complete cycle returns 750.47 kWh from 852.80 kWh input, giving 88% efficiency. The 102.34 kWh difference is conversion loss in this simplified model.
Compare charge and discharge totals only after accounting for the change between initial and final stored energy. A run beginning with a full battery can export energy that was charged before the displayed study period.
Keep the grid balance consistent
During an illustrative 1,200 kW load, 750.47 kW discharge leaves 449.53 kW of import. At a 400 kW load, export mode produces 350.47 kW of export. Self-consumption mode instead caps discharge at the load.
The built-in load profiles are synthetic. They are useful for learning the tool, but cannot establish your building’s demand savings. Uploaded hourly demand remains hourly information even if you choose 15-minute simulation steps; repeating each hourly value does not recover hidden peaks.
Before relying on a dispatch result
- Use compatible units and keep SOC limit enforcement enabled for feasible dispatch.
- Inspect the earliest interval where the requested schedule is clipped.
- Check initial and final SOC; do not count pre-existing stored energy as recurring revenue.
- Ensure charge and discharge windows do not unintentionally overlap; the first matching rule takes priority.
- Validate timestamps, missing readings and units in uploaded profiles.
The lab does not model tariffs, demand-charge ratchets, PV production, degradation cost or temperature-dependent efficiency. A schedule called “solar charging” is still a commanded charge window; the tool does not prove that solar energy is available during that window.
Sources and scope
- U.S. DOE: Solar energy and storage basics ↗
Storage losses and shifting energy in time. The SOC and grid-balance calculations above document this tool’s model.
Reference links provide technical context; the worked examples and interpretation are specific to this guide. No external source certifies these tools.