Select, the plant division of Laing O鈥橰ourke, has adopted Punch Flybrid鈥檚 high-tech flywheel system to save fuel and carbon emissions.
Because flywheels store kinetic energy, construction sites that use them do not need such large generators. The generator used to power a tower crane, for example, is generally specified to cope with peak start-up loads; most of the time it is bigger than needed. A flywheel can store enough energy to meet the spikes in demand, and a smaller generator does the rest.
Select Plant Hire has had a 66-tonne Terex CTL1600 luffing tower crane at work on a site in London. It initially set it up with a 500KvA generator set combined with the Punch Power 200, instead of a 800kVA generator specified by the crane manufacturer. This saved 1,300 litres of fuel over 213 operating hours, or about six litres an hour 鈥� a 50% saving.
But it was able to downsize the generator further, attaching the crane and flywheel to a 320kVA genset.
Select has calculated that the crane is now saving more than 30,000 litres of fuel every 3,000 hours 鈥� 聽10 litres per hour.
Select managing director Alex Warrington said: 鈥淚t is quite staggering when you see the environmental savings this technology can have on just one crane. At Select we are proud to be leading the way in something that could easily be integrated to cranes not just across the UK, but the world and make a significant impact on CO2 辫辞濒濒耻迟颈辞苍.鈥�
Select鈥檚 data mirrors that recorded by Bowmer & Kirkland at Manchester Metropolitan University, where it has two tower cranes on hire from Select. The crane manufacturer specifies a 300 kVA generator for each crane. Bowmer & Kirkland is using 150 kVA generators instead, with a Punch Power 200 unit attached to each, on hire from Stuart Power.
As a result, reveals Bowmer & Kirkland group crane manager Dave Shooter, the contractor is saving 60,750聽 litres of diesel fuel per crane over the 45-week crane hire contract. That 121,500 litres of total fuel saving equates to 318,330 kg of carbon saved.
In terms of hard cash, the savings have risen as the price of fuel has gone up. Subsidised red diesel was 55p per litre at the start of the hire, making a saving on fuel of 拢66,825.
Bowmer & Kirkland makes a further 拢18,000 saving by hiring smaller generators, although there is the additional cost of hiring the Punch Flybrid boxes.
The higher the price of diesel, the more money is saved. So when the construction industry loses access to red diesel in April 2022, the commercial appeal of the technology will grow further. Were Bowmer & Kirkland paying an unsubsidised 拢1.40 a litre on this job, for example, the Flybrid units would be saving it more than 拢170,000 in fuel costs.
Punch Flybrid managing director Tobias Knichel said: 鈥淥nly through team work it is possible to achieve these outstanding environmental results. Everybody at Punch Flybrid is happy to be working with Select Plant Hire and to realise bigger and bigger fuel, emission and operating cost savings.鈥�
[See also our feature on Punch Flybrid in the November 2021 issue of ]
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