Understanding hybrid systems
17 May 2023
The benefits and hire opportunities that can be achieved from hybrid power systems were discussed in a fascinating webinar organised recently by the manufacturer POWR2.
Sales Director Frank Moyer, who has previous work experience in the power generation hire industry, explained that hybrid power systems combine two or more technologies to increase system efficiency, such as a battery energy storage solution like POWR2’s Powrbanks, in tandem with a diesel generator or solar panels.
The battery energy storage system has three main components, namely an onboard controller or computer, industrial grade inverters and high-density batteries which, in POWR2’s case, are lithium-ion phosphate units.
Excess power from the generator charges the battery and when full the generator switches off, leaving the battery to provide power silently. When the charge level is almost depleted, typically to 10 per cent of capacity, the generator restarts.
“In an ideal application, the diesel generator is only going to run a few hours a day to charge the battery and then, based on the load, the battery will run for, say, 20 hours,” said Frank Moyer.
He explained that diesel generators have traditionally been sized according to peak load requirements but, as most load profiles are uneven, the machines are typically oversized. This can lead to unnecessary fuel consumption, excess emissions and greater maintenance requirements.
One case study cited was a fully sustainable installation where a Powrbank was used to power a crop irrigation system in a location without access to grid power. Using a diesel generator had previously required manpower to switch it on and off and regular service call-outs, but using the battery unit in tandem with solar panels, the genset was rendered unnecessary.
The system is also controlled remotely and operating data can be collected regarding carbon emissions and other parameters.
In another project for a golf tournament event (pictured), a 15kVA Powrbank was paired with a 60kW diesel generator to power a concession stand running fridges, freezers, menu boards and lighting. “The system was able to support the load for six hours at a time, with the generator turning on for an hour or two to recharge the battery,” said Frank Moyer.
“The event organiser loved the silent power as it was a televised event.”
He added that fuel costs can be reduced in some cases by up to 70 per cent.
Regarding hire rates for such equipment, Frank Moyer suggested that a hire company could charge a monthly rate of 4 to 5 per cent of the purchase cost of the battery bank. The machines are virtually maintenance-free and the LFP batteries are rated for 6,000 charge cycles, with one cycle per day. This enables POWR2 to give a ten-year warranty on the units.
To find hire opportunities, hirers could identify sites where a generator under 100kW is running for longer than a single shift to see if the load could justify adding a battery unit. Some existing contractors might benefit from adopting the technology, especially companies who prioritise sustainability and where the system would be in use for three months or more.
Up to four Powrbank batteries can also be connected in a parallel arrangement, as reported previously on the blog, to provide greater power outputs.
● Picture shows the Powrbank golf tournament installation provided by POWR2.
