Load Share, Load Balancing and Peak Shaving – What’s What?

How Does Load Share Work?

With load share, both active power and reactive power (also known as reactive load) are evenly distributed across multiple power sources. These may include, for example, a battery pack in combination with the grid, or a generator in combination with a battery pack and the grid. This means load share is only used when there is more than one power source. Load share ensures that these different sources supply power proportionally to their capacity; the load on each supply source is exactly equal.

Previously, load share was often used when multiple generators were connected in parallel. The load was then evenly divided over these machines. Nowadays, we increasingly see it applied in the grid, for example in combination with a battery pack and the Blue Hybrid Box.

When Is Load Share Applied?

Load share is used in many different ways. As described above, it only happens when there is more than one power source. We have applied it in the grid (for example, during synchronous grid takeover), in industry, and in hospitals.

Load share is a great way to handle large loads with smaller machines and to ensure operational reliability.

All emergency power units from Voet Energy Solutions are equipped with a DEIF control system, enabling all these machines to operate in load share mode.

Benefits of Load Share

Load share increases reliability, as this technique helps prevent overloading. It also offers the user flexibility – power can be easily scaled up or down remotely.

Another advantage is the ability to “build modularly” with emergency power solutions. Multiple machines can be linked together effortlessly. This can also benefit transport: in some cases, four smaller units are easier to transport (and place) than one large one.

What Is Load Balancing?

Load balancing prevents overload and ensures the most efficient use of machines and power distribution. As we know, every energy solution has a maximum power capacity that can be used at one time. With load balancing, the connected power sources deliver a preset percentage of the required power. When one source, such as the battery pack or the grid, exceeds this percentage, the system balances it out using another power source via software control.

The software can be configured so that the power percentage delivered varies by hour. For instance, during peak energy demand at 07:00 in the morning and 18:00 in the evening, a higher power output can be set than during quiet nighttime hours.

Benefits of Load Balancing

Like load share, load balancing improves reliability – by setting a maximum percentage of capacity in advance, overload is prevented. In addition, load balancing allows for easy configuration of which machine supplies the most power. This optimises fuel consumption, increasing efficiency. Load balancing can also be used to limit machine runtime. For example, we can choose to draw most of the power from the battery pack and minimise generator operation.

When Is Load Balancing Applied?

In a hybrid setup, load balancing is an effective way to distribute power so that energy consumption or emissions can be optimised. This results in cost savings and reduced CO₂ emissions.

What Is Peak Shaving?

Peak shaving (also called “peak clipping” or “trimming”) is a form of load balancing. This technique continuously matches supply to demand. The “peak” refers to the consumption peak – the maximum demand from the users. Peak shaving reduces these peaks by using additional power sources such as generators or battery packs. This results in a more even electricity demand throughout the day for the main power source, often the grid.

When the software detects that consumption is within 5% of a preset limit, it can bring an additional power source online, either fully or in steps.

Benefits of Peak Shaving

When applied to a mobile emergency power installation, peak shaving can reduce costs. For example, grid operators often charge significantly higher rates when the maximum contracted power is exceeded.

By adding a battery storage system to the emergency power setup, energy can be stored until the grid limit is reached or the battery is full. During busy periods, any demand above the preset limit can be supplied from the battery. This eliminates the need for additional power sources, saving significantly on fuel costs and lowering CO₂ emissions.

When Is Peak Shaving Applied?

Peak shaving is particularly useful when there are transmission limitations or if the grid connection is too small. The remaining capacity can then be drawn from the emergency power installation. In advance, it’s easy to set the maximum power that can/may be taken from the grid, with the rest coming from, for example, a battery pack.

Peak shaving is also applied when solar panels are connected to the installation. In this case, it works in reverse: the solar panels supply most of the demand, and only when solar generation is insufficient will other power sources be used. This way, the solar panels cover the majority of the load.

The Technology Behind It

These so-called Power Management Systems are built into the DEIF control systems of our emergency power solutions (such as the battery pack and generator). A communication network ensures that the machines are connected to each other, allowing control systems to exchange information about load, available capacity, and even build a smart grid installation.

The data collected by the DEIF control system is used to calculate how many power sources are available and which are in use. Based on this calculation, the system can also issue commands – for example, opening or closing circuit breakers, or starting and stopping machines.

This smart system can also detect whether all power sources are running smoothly. If one of the emergency power solutions becomes unstable or unavailable, the system can take action to prevent a complete power outage.