Quick answer
No. Peak shaving, backup reserve, protected loads and other agreed site needs must come before trading. Record how much battery power and energy the site needs to keep, when those rules apply and who can pause trading. The trading software should only use what is left after those limits are protected.
Protected site needs, like backup reserve, peak shaving, critical loads or protected operating periods, must take priority over trading activity. Before the aggregator, VTP or control provider enables trading on the battery, the installer or commissioning engineer should record:
- How much battery power the site needs to keep
- How much stored energy it needs to keep
- When those rules apply
- Who at the client’s site can tell the provider to pause or reduce trading
The provider should then configure the battery control software to follow those recorded site rules before it sends trading commands.
Record the site constraints before trading starts
The aggregator, VTP or control provider must configure the control software so it does not send charge or discharge commands outside:
- BMS safety limits
- Inverter charge and discharge limits
- Minimum and maximum state of charge
- Warranty and cycling limits
- Agreed import and export limits
- Any G100 export limit
You should also record and send the aggregator, VTP or control provider the detailed site rules, including:
- The minimum reserve in kWh or state of charge
- Any discharge power in kW needed for peak shaving
- Which site peaks the battery should try to cover
- Protected production periods or critical loads
- The named client contact who can tell the provider to pause or reduce trading
- What the provider should do after that person asks for trading to pause or reduce
If the customer wants backup, record how much stored energy they want to keep in the battery, in kWh or state of charge.
Do not treat that reserve as usable backup power unless the installation has the right islanding, changeover and protection equipment. Even then, the battery can only provide backup if the installation can disconnect safely from the grid and feed the protected loads.
How GridVolt sets charge and discharge commands
GridVolt uses Energy Manager to send charge and discharge commands to compatible batteries and inverters installed at the client’s site. Before GridVolt sends a command, Energy Manager checks the tariff, site load, solar output, state of charge and the reserve rules recorded for that site.
For example, if the forecast shows that there will be plenty of solar tomorrow, GridVolt may make more stored energy available for trading today, because the battery is likely to recharge tomorrow. But if the forecast shows low solar output or a high import period, GridVolt may hold back more stored energy for use on the site.
When describing how the system operates to the client, set it out in this order in your proposal:
- Hard equipment limits and grid connection limits come first.
- Customer site rules come second. These may include peak shaving, backup reserve, solar storage or protected operating periods.
- GridVolt can only use what is left for trading.
The proposal should show how much battery power in kW and stored energy in kWh is kept for the site, and how much GridTrade can use.
What to avoid promising in the proposal
Do not suggest that a fixed amount of kW or kWh will always be available for trading as factors like site demand, solar output, state of charge, import limits, export limits and customer reserve rules all affect it.
GridTrade measures the import or export change on the site’s half-hourly grid meter, not on a separate battery meter. If site demand changes during a trade, the meter reading can change too. So do not promise that the meter will show the battery’s trading action on its own.
Say that GridVolt will check the customer’s reserve, peak-shaving needs, protected loads, import and export limits and override rules, then configure GridTrade to use only the battery power and stored energy available for trading.
Before GridVolt enables GridTrade, send GridVolt the site reserve, protected loads, override rules and any limits that should reduce trading availability.
Related questions
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