Today’s energy grid is facing an unprecedented set of challenges, and there is a need to consider energy conservation and increased efficiencies, including renewable energy sources.

Localised usage has also had an impact on increased electrification demand – due to the increased adoption  of electric vehicles, home applications,  and other devices – that is consequently creating unprecedented stress on existing infrastructure and instability.

With this in mind, we are increasingly being asked if battery systems are at a point that make them an important and viable option for commercial sites – we believe the answer is yes, when integrated with a hybrid system.

The present-day mobile battery energy storage system allows the on-site storage of electrical energy from multiple sources – a hybrid power system incorporating:

• Solar, or other renewable sources, and
• a generator or the grid

This stored energy can then be redistributed at a later time to suit the site’s or application’s particular power needs.

With a battery energy storage system deployed onto a site, it is possible to have a clean, green solution that can power the site during those periods of low energy demand, such as overnight or during the weekend.

This allows customers to utilise reliable, green, clean energy in almost any application to reduce fuel consumption and CO₂ emissions.

Example 1: a typical off-grid application

The hybrid power system manages the operation of the generator.

• When power demand is low the generator turns off. Then,
• when the battery runs low, or power demand increases, the generator turns on

The result is less running hours, more efficient consumption of fuel, less emissions, and reduced maintenance.

Example 2: a typical hybrid solution 

In any demanding application like events and construction sites, where low loads or peaks can be a problem for a smaller capacity generator, the hybrid solution is ideal to improve the overall performance of the site.

Hybrid power systems manage the operation of your generator much like off-grid applications, but the battery storage:

• can be utilized to instantaneously provide high power demands, above the generator’s normal capacity for short periods, or
• provide lower levels of power silently from the battery system alone.

The battery system can also be topped up with renewable energy sources to further increase battery autonomy.  The result is less running hours, more efficient consumption of fuel, less emissions, and less maintenance.

 Hybrid solutions are indeed ideal to convert traditional technologies into greener solutions, with a significant cost saving and a low environmental impact.

This technology is compatible with most diesel generators & can be provided with lead acid or lithium ion battery systems.

Emerging Usages

• Construction sites: such as site huts & amenities, or in locations where power is not connected to the site
• Electric Vehicle (EV) charging sites, with single or multiple charging ports: especially beneficial for establishments that have a ‘green initiative’, fleets of EVs and a considerable solar system.
  • A hybrid solution overcomes the problem of the Fleet EVs draining their power during the workday when the solar system is working at its most productive. With no EVs to utilise this ‘free’ power during a typical workday, it is possibly exported to the grid at a very meagre feed-in tariff.

At the end of the day when these EV Fleets return to their base and need a recharge, the solar system is at reduced or zero output – forcing the EV fleets to charge from the electricity network – typically at a time of the day that coincides with peak energy costs (as the network is at its peak time).

By capturing the site’s solar energy into battery storage, organisations can optimise utilisation of their energy generation, and this can then be used to recharge the EVs with the solar power generated during the day.

• Remote locations: such as off-grid or regional locations with generators and/or renewable energy already in place
• Events such as: concerts, corporate events, and outdoor function venues
• Utilities, even including those with integration into the electricity network – for the better support of smooth energy flows
• Customer-side storage systems that are connected to the distribution system on the customer’s side of the power meter. In-front of the meter offers more integration into the electricity network and supports smoother energy flows.

Varying  volume needs and battery usage – the ‘bucket’ analogy

The capacity or volume of power usage that is best suited to battery integration can vary, and is  dependent upon battery bank size, and whatever the battery is rated at in amps (current flow) / kW.

Duration is also important to consider, and the extend of time the battery can supply varying volumes of energy need will be dependent upon the quantity and  amount of storage. Basically, think of the battery as a ‘bucket of energy’, the ‘bucket’ is full when batteries are fully charged, the site load drains energy from the ‘bucket’.  The bigger the hole or drain in the side of the ‘bucket’, the bigger the load hence the ‘bucket’ is emptied quicker, alternately a small ‘hole in the bucket’ results in energy usage at a lower volume and will last longer. This is referred to as battery autonomy.

Other power sources can continue to ‘top-up’ this ‘bucket’ whilst it is being drained to increase the autonomy of the ‘bucket’. When the generator is operating and  providing power to the site it is also charging the batteries (filling the ‘bucket’).

Should the site load peak at a level greater than the generator’s rating, the ‘bucket’ of stored energy can assist the generator by emptying to supply this excess load – above the generators normal rating – until the ‘bucket’ is emptied or refilled.

For example, a 50kW generator can supply a maximum of 50kW to the site load, which may be quite suitable for 80% of the time, but occasionally the site load may peak to 70kW. Adding a suitable battery storage system can supply this excess load for a period, based on its rating and autonomy.

When the site load drops back below the generator’s rating of 50kW the battery returns to charge mode and restores its autonomy-time ready for the next increase.

Similarly, as the site load drops to low levels, say overnight, the generator can turn off & the batteries can silently provide power to the load until they are discharged or the site load increases above set thresholds.

This system and approach can reduce the overall size of the generator, fuel consumption & maintenance costs and as well as reduce operating times, and provide silent power from the battery system.

Keen to explore generator and battery integrations? Contact the PGS team today.