Case study - Commercial solar and battery systems combined with the wholesale market

Written By Anders Jensen

Combining a solar and battery system along with buying and selling electricity on the wholesale market results in outstanding value for the system owner. The wholesale pricing plans offered by companies such as Amber allow the home or business owner to turn their conventional electricity plans on their head by giving the customer the ability to buy electricity and sell electricity depending on what the wholesale price is doing. There is no flat rate charges rather a fluctuating feed in rate ( for solar) and a fluctuating usage rate ( for appliance usage).

The idea with installing a solar and/ or battery system and connecting to the wholesale network basically revolves around the ability to conduct ‘ energy arbitrage’, the act of buying electricity when the price is low, storing it in your battery for use later when the price is high and also for selling back to the grid when the price is high.

Depending on your energy usage, whether it be small residential ( 15kWh usage per day of electricity) or small to medium commercial ( up to 270 kWh usage per day of electricity), using a battery can have massive financial returns in the currently wildly fluctuating electricity market.

Wholesale electricity price graph

Fluctuating wholesale electricity price

So how can a solar and battery system combined with wholesale prices help you earn a return on your system?

  1. If you have a large solar system (10kW to 100kW) and small daytime power usage:

    1. So potentially what a battery and solar installation owner can do is store your excess solar when the export price is close to zero during the middle hours of the day (10am-2pm) and sell the excess solar when the export price is close to 15c/kWh at 8pm. So in the first case you make $6 a day from your exports if you have a 40kWh battery and a 10kW solar installation

  2. If you have a large battery ( 40-100kWh battery capacity), with little or no solar installed:

    1. Similarly, if you have a high usage site or only have a battery, you can charge your battery for 10c/kWh for example between 10am to 2pm and use this power around 8pm when the import price might otherwise be 30c/kWh. If you charge a 40kWh battery from empty to full in this way then the savings would be around $8 a day.

So the idea in the latter case would be to have a 40kWh battery for cases where you only use 20kWh a day, you can charge your battery during the middle of the day to full capacity and use half the capacity to power the house or business for the next 24 hours and use the other half of the capacity to sell power back to the grid. There is no extra work for you as the Amber algorithm automates the buying and selling of electricity.

Contact Anders on 0478 285 918 to get a custom report showing savings potential at your site.

Anders Jensen