Paying for electricity when it’s at its most expensive hurts your bottom line. With commercial energy optimisation, you can cut your power costs without disrupting work at your site.
In this article, we explain what energy optimisation is, how it works, how much you can save, and what to ask an installer or EPC.
What is energy optimisation?
Energy optimisation is changing how and when your business uses electricity to cut its bills. Sometimes, that means using less, but it can also mean moving some of your electricity consumption to a cheaper time.
For example, take a cold store at a hotel or care home. The food must stay at a safe temperature all day to meet safety rules.
Here’s how you’d optimise when a cold store uses electricity. Before electricity gets expensive, make the cooling system work harder so the temperature falls towards the lower end of its safe range. When the price goes up, turn the cooling down and let the temperature rise slowly.
As long as you keep the food within a safe temperature range, you get the same result but pay less for electricity.
If your site has solar panels and a battery, you may be able to save more by charging the battery with spare solar electricity, then using it later instead of buying electricity from the grid when prices are high.
How is energy optimisation different from energy monitoring, energy efficiency and energy management?
The differences between energy monitoring, energy efficiency, energy optimisation and energy management are:
| Term | What it means |
|---|---|
| Energy monitoring | Collecting and checking meter readings to find out how much electricity the site used and when. Readings from individual pieces of equipment can show how much electricity each one used. |
| Energy efficiency | Using less electricity to keep a commercial site lit, heated, cooled and running, often by repairing old equipment or replacing it with equipment that uses less power. |
| Energy optimisation | Changing when the site uses or stores electricity so the business can pay less for it. |
| Energy management | Measuring, planning and controlling energy use across the whole site. This can include monitoring, reducing how much electricity the site needs and moving some electricity use to cheaper times. |
How does energy optimisation work?
An energy optimisation provider uses energy management software to manage this work for the business.
Energy optimisation software calculates when compatible equipment should run, but your business decides what must remain available.
For example, you may require a minimum amount of electricity to stay in the battery, an EV to reach a set charge by its departure time or production equipment to keep running during time-critical work.
Here’s how the process works:
1. Connect the meters and equipment
The provider first checks that the site’s meters can send the readings its software needs and that the equipment can receive its instructions. It then connects the compatible meters and equipment to the software.
It also connects a controller, which passes readings to the software and instructions to the equipment.
Before starting the service, the provider checks that the readings and instructions are getting through.
2. Work out what to do
The software receives the latest readings from the meters and equipment, showing it your current electricity use, solar production and battery charge level.
It also gets current electricity prices and, where available, forecasts of how much electricity the site will need and how much your solar panels will produce.
With this information, it calculates whether a battery should charge or discharge and whether the business could save money by running other equipment at a different time or using less power for a while. It may decide to do nothing at all and let everything carry on as it is, if there are no options that save your business money.
3. Send the instruction and check the result
Once the software has worked out what to do, it sends an instruction to the controller, which passes it to the equipment. If the instruction is for the battery, the inverter controls how much electricity flows into or out of it.
The meters and equipment then record the result, so the provider can check whether the instruction had the expected effect. The software uses the new readings the next time it checks whether changing anything could save money. It may send a different instruction if the site is now using more electricity, the solar panels are producing less than expected or electricity costs more than before.
What can a commercial site optimise?
A provider can only include equipment your business can run differently without affecting safety, comfort or work at the site. Your business decides which limits the provider must follow.
The table shows what the provider may change and the limits that still apply:
| Equipment | What the provider may change | What your business must still get |
|---|---|---|
| Battery | When and how quickly it charges or discharges | Enough stored electricity for the site, without breaking the battery warranty or the site’s grid limits |
| Solar panels and battery | How much spare solar electricity the battery stores for later | The agreed amount of electricity kept in the battery for the site |
| EV chargers | When the chargers run and how much power they use together | Each vehicle charged to the required level by the time its driver needs it |
| Heating, cooling and ventilation | When the equipment runs and how hard it works | Safe temperatures, suitable air quality and the conditions agreed by the business |
| Other high-power equipment, such as pumps, compressors or production machinery | When approved equipment runs and whether several items run at once | Production targets, safety rules and any work that must finish by a set time |
If your site has a building energy management system (BEMS), staff may already use it to control heating, cooling, ventilation and other building services from one place. The provider may be able to connect through the BEMS instead of adding separate controls to each piece of equipment.
Where do the savings come from?
Most savings come from energy arbitrage, which means moving electricity use to cheaper times. Some businesses may also use peak shaving to cut other charges on their bill or avoid extra connection work.
Only count a saving if it lowers your bill or avoids a cost your business would otherwise have paid.
| How your costs may fall | What happens at the site | What you need to check |
|---|---|---|
| Use electricity at cheaper times | The provider runs approved equipment or charges the battery when electricity costs less. The battery can then supply the site when grid electricity costs more. | Check whether the price difference is large enough to make the change worthwhile. |
| Use more of your solar electricity | The battery stores solar electricity the site can’t use straight away, then supplies it later instead of the site buying electricity from the grid. | Compare the grid price the business avoids with the export income it gives up. |
| Reduce chargeable peaks | The battery supplies some of the power the site needs, or the provider moves approved work to another time, so the site takes less electricity from the grid at once. | This only cuts the bill if the electricity contract includes a charge that falls when the peak is lower. |
| Make better use of the existing grid connection | The provider spreads EV charging and other high-power work across different times instead of running everything at once. | This may keep the site within its import limit or avoid some grid connection work. It won’t always reduce the electricity bill. |
Any calculation involving a battery must allow for electricity lost during charging and discharging, as well as extra battery wear. If those costs are greater than the saving, leaving the battery alone costs less.
Can energy optimisation earn income as well?
For suitable sites in Great Britain, a provider may also use spare battery capacity to earn income from electricity markets or flexibility services. It can only use capacity left after the site’s own needs have been covered. The provider must also check that the meter, equipment, grid connection and contracts meet the rules.
Keep this income separate from bill savings because the amount can change. It is a secondary opportunity, not the main purpose of energy optimisation. GridTrade does not currently offer it in Ireland.
How do you get started with energy optimisation?
Ask an energy optimisation provider to look at how your site uses electricity. They can then work out whether changing battery charging times or when other equipment runs could cut your costs.
Show the provider how your site uses electricity
The provider will normally need:
- At least 12 complete months of half-hourly data for each meter
- The prices you pay for electricity at different times and the amount you receive for exports
- Records showing how much electricity your solar panels produce
- The amount of electricity your battery can store and how quickly it can charge and discharge
- The times EVs must be charged, the temperatures heating or cooling must maintain and any production deadlines
- The amount of electricity you need to keep in the battery for the site
- The site’s import and export limits
- Planned changes, such as new EV chargers, heat pumps, machinery or opening hours
Ask how much you could save
There’s no reliable percentage that applies to every business. The provider should base its estimate on your actual electricity prices, site use, solar production, equipment limits and how much electricity use can move to a cheaper time.
The estimate should include the cost of the software, controller, installation and support.
Ask to see every price, cost and assumption used. The provider should compare your current electricity costs with what it expects them to be after energy optimisation.
Check the service before you sign
Ask the provider:
- How often will the software recalculate the battery’s charging and discharging times and when other equipment runs?
- Can you see when the battery charged or discharged and when other equipment ran?
- Can your business change the agreed temperature limits, charging targets, production times or battery reserve?
- Who will deal with faults or incorrect readings?
- What will happen to the equipment if the software loses its connection to the site?
Start your energy optimisation project with GridVolt
GridVolt provides commercial energy optimisation services to end users and installers across the UK and Ireland.
If you run a commercial site, GridVolt can examine how you use electricity and what you pay for it, then estimate how much GridVolt Energy Manager could save you.
If you’re an installer, GridVolt can model energy optimisation as part of a new solar or battery project. This lets you show the client how Energy Manager could change the savings and payback before they buy.
After installation, Energy Manager recalculates when connected batteries and other equipment should run every 15 minutes. At one agricultural site, this increased the savings made by an existing battery by 41% during its first 70 days. This was a 41% increase in the battery’s savings, not a 41% reduction in the site’s whole electricity bill.
For suitable sites in Great Britain, GridVolt can also use battery capacity left after the site’s needs have been met to earn trading income through GridTrade. GridTrade isn’t currently available in Ireland.
You can send GridVolt your site details or information about a client project using the form on the right. The team can examine the figures and show you what energy optimisation could achieve.
Energy optimisation: frequently asked questions
Can GridVolt work with equipment already installed at my site?
Yes, as long as the equipment is compatible. GridVolt can connect Energy Manager to many third-party batteries, inverters, solar systems, EV chargers and heat pumps. It can also connect through a building management system where the systems are compatible.
GridVolt will need to check the make, model and way each piece of equipment sends and receives information before confirming what can be connected.
Do I need to change my electricity supplier?
No. GridVolt works alongside your existing electricity supplier, so you don’t need to change your supply contract to use Energy Manager.
Your current tariff still matters because Energy Manager uses the prices you pay when it calculates the cheapest times to charge a battery or run other equipment.
Can I see how Energy Manager is working?
Yes. You can use its web and mobile dashboards to see current and past information from your site.
This can include how much electricity the site used, how much the solar panels produced, how much electricity the battery held and when connected equipment ran.