It is often believed that installing energy storage systems will immediately reduce electricity bills. This is partly true—we store electricity when it’s cheaper and use it when it’s more expensive or when we need more. However, business facilities require smarter solutions, which is where the Energy Management System (EMS) comes in. Factory settings do not account for the facility’s current needs, whereas the EMS can assess electricity prices, consumption, power demand, and storage levels, and align the storage units' physical capabilities with the facility’s needs in real time.
EMS is a smart storage management system comprising software and control hardware, connected to storage units, inverters, meters, and a communication network. This allows the energy management system to receive data and send commands to storage units and related equipment. If the storage units operate in conjunction with a solar power plant, the EMS can direct excess energy generated by the solar power plant to the storage units. This energy is used later, when solar energy production decreases or when electricity prices are higher. This way, a larger share of the generated energy remains on-site.
Charging from the grid and electricity price fluctuations
Batteries can be charged from the electricity grid, which is particularly relevant for companies whose electricity costs are linked to prices on the Nord Pool exchange. Electricity prices can vary significantly throughout the day, so it is very important not only how much electricity is consumed, but also when it is purchased.
EMS can schedule the operation of storage units so that electricity is purchased and stored during cheaper hours. This energy can then be used on-site when electricity is more expensive or when the load increases. Managing this mode manually is complex, as it requires monitoring electricity prices, consumption, battery charge levels, and the facility’s power demand simultaneously.
Without an EMS, storage units can charge according to a schedule but won’t know that electricity will be even cheaper in a few hours; they may discharge too early, even though it would be more beneficial to save the energy for a higher load. An EMS helps maximise the potential of storage units.
Reducing consumption peaks
Electricity costs in business depend not only on kilowatt-hours consumed, but also on instantaneous power demand. When multiple pieces of equipment turn on at the same time, the facility draws more power from the grid, creating a peak—the moment of maximum load. The peak itself is not a problem as long as it does not increase costs or bring the facility close to its power limit. However, if the storage units do not assist at that moment, the company draws the entire load from the grid, increasing power-related costs, even though part of the load could be covered by the storage units.
EMS monitors energy consumption at the facility and can begin using stored energy when the load approaches a set limit, thereby reducing the amount of power drawn from the grid. Such energy management is relevant for manufacturing, warehousing, logistics, retail, and other facilities where daily loads are not uniform.
To reduce peak demand, storage units must be charged at the right time and ready to operate as soon as the load begins to increase. If storage units are managed solely by general settings, they may begin operating only after the facility has already drawn the maximum amount of power from the grid.
EMS can also be important when a facility is subject to limits on the power or energy it can feed back into the grid. In such cases, the control system helps monitor the set limits and manage the operation of the storage units, ensuring the equipment operates within the limits specified in the technical conditions.
How to Prepare for EMS Installation
The EMS only works when all the equipment is compatible. Therefore, when selecting storage units and other equipment, it is important to ensure they are compatible with the EMS, can transmit the necessary data, accept commands, and maintain a reliable connection at the facility. The EMS must continuously receive data from the equipment and transmit commands to the accumulators, so it is necessary to determine before installation whether an uninterrupted internet connection will be ensured at the site. The most common consideration is which is more suitable for a specific site - a wired LAN connection or a wireless (4G) connection. If the connection is unstable, the management of the storage units may become less accurate.
It is advisable to plan EMS management before selecting the batteries and other equipment. It is important to evaluate specific data: the planned storage capacity and power, inverter manufacturers, technical documentation, connection to Nord Pool prices, ESO limits, and hourly consumption data. It is also important to know in advance what the most relevant use of the storage units will be—for internal electricity needs, peak load management, charging from the grid during off-peak hours, storing energy generated by a solar power plant, or multiple functions simultaneously.
Pinus LT helps tailor EMS management to the facility’s needs and integrate the equipment into a unified energy management solution. Contact us - we’ll discuss your situation and help you decide what management logic your facility requires.