How profitable is a battery for Pottie's Gat Solar Park?

Storing energy in times of negative energy prices

The idea arose to install a battery near the solar park that can store the energy in times of adverse market conditions, and then sell it at favorable times. To test the technical and financial feasibility of this, Bas called in QING.

Method of feasibility-
battery research

Collecting data from Pottie's Gat Solar Park

After setting the principles, the project started collecting data. Thanks to our previous cooperation with the Booijink family for the realization of the solar park, we were able to see the energy output of the solar park fairly easily. This was supplemented with energy market data to determine the battery's sales potential and trading opportunities.

Determining influential variables

There are countless variables and knobs to turn on in complex energy systems like this one. The trick is to distinguish between the main and the secondary issues so that the analysis can be kept understandable and manageable.

Because we have determined crucial variables we limit the complexity and scope of the research without compromising the result. For example:

• What is the storage capacity and capacity of the battery that we are going to investigate?
• In which cases does storing energy in the battery take precedence over supplying energy from the solar park?
• Which energy markets do we include and do not include?

By making the research less extensive, we prevent the Booijink family from spending a lot of time in analyses that ultimately prove to be of limited added value. This is how we keep the feasibility study efficient and effective.

Simulate how the battery behaves in the physical world

To calculate whether the Booijink family would do well to invest in a battery, we created a simulation. This allows us to test how the battery would behave in the real world with the current market conditions and deduce whether that would be profitable. The simulation continuously calculates which revenue models yield the most based on the battery's fill rate, the changing yield of the solar park and market conditions. For example, it is decided when is the right time to sell stored energy or to provide balancing services to the grid.

Based on the test period, we have 4 optimal business models and combinations of these identified, including the earning potential in turnover per year. These are set out in a profit and loss account that categorizes all costs and revenues by year.

Result: battery probably not profitable in today's market

• The profit and loss account showed that the battery would only be profitable after 14 years, but after 15 years, the battery was depreciated.
• The grid connection cannot be fully used by the battery, because the solar park is also connected to the same connection. This means that the battery is limited in the trading strategy, so that the battery can generate less turnover compared to a scenario where the battery would be connected to the grid alone.
• The energy markets show significant price fluctuations. It is unclear how the energy markets will develop in the future, so the uncertainty in the earning potential of energy trading through the battery is considerable. This makes the payback period difficult to estimate.

Realize the battery in the future

Expecting a losing business case is also a valuable outcome for the Booijink family. With this they prevent them from now investing in something that turns out to be unprofitable.

This does not mean that this business case will not be profitable at a later date. Batteries are becoming increasingly cheaper and regulations concerning energy taxes and other cost items are constantly changing. In addition, if the market develops positively, the battery can still be realized.

The research also provided insight into the factors that determine battery revenues and costs and how changing market conditions influence the business case.

It's not now or never, but now or later. The Booijink family knows under what circumstances it can work out financially. eWith this knowledge, n is ahead of other solar parks.