by Ben Vincent, National Account Manager, Construction, for Northern Europe at Aggreko
There are a number of issues that arise when it comes to construction site power generation. I’ve picked out five factors to consider when it comes to choosing the right power generation for your site.
1. Demand
Construction sites often have variable power demands that differ during operational and non-operational times. Power demand variances can lead to generator inefficiencies and having the ability to optimise power output is essential. For example, we’re seeing hybrid power being used more frequently. A generator will meet larger peak-time power requirements and charge the hybrid’s battery, the hybrid then takes over during periods of lower demand, reducing the need for the generator to operate at an inefficient, low load. With the hybrid unit subsidising generator power, fuel consumption is reduced, improving the fuel efficiency versus power output and reducing operational costs. It’s easy therefore to see why hybrid use is proving popular.
On the other hand, if base power demands are too high for a hybrid option, ‘load-on-demand’ generation is another option. This scalable alternative uses smaller kVA generators to power the same peak demand as a single larger unit but with the option of turning surplus generators off when the site’s demand falls. As the generators switch on and off automatically to produce only as much power as the site needs, this can be much more fuel efficient. An uninterruptable power supply is guaranteed even during generator maintenance, whilse operating costs and emissions are also reduced via lower fuel consumption.
2. Noise
Local authorities require construction sites to use the most practical measures possible to control noise and vibration, as defined in Section 72 of the Control of Pollution Act 1974. However, a number of ways construction sites can minimize the noise caused by power generation. Sourcing silent generators with a low level of dBA can be effective whereas using acoustic curtains, which can be fitted to fencing around the generators, can reduce noise by around 10 per cent. Using hybrid power units as a silent power alternative to generators can be beneficial but only when low electrical loads are needed. Load-on-demand set ups will also ensure a fall in noise levels when the site’s power demand drops and fewer generators are needed.
3. Emissions
In the UK, there is mounting pressure on the government to tackle air pollution. This has led to many local authorities and city administrations introducing tighter emissions controls for construction sites. However, a number of greener options to choose from when selecting site power, especially in larger cities. Gas-fuelled generators can cut emissions by up to 40 per cent, compared to diesel and will improve a site’s carbon footprint, though it is recommended to check the fuel efficiency when specifying gas generators. Biofuels, diesel generators with diesel particulate filtration (DPF) units and hybrid power units, can all help to significantly reduce emissions. Finally, using smaller generators to load share rather than one larger generator, can also significantly reduce emissions and save fuel. Aggreko can offer all of the above options.
4. Security
The security of generators and supporting equipment can be a serious issue in remote locations, unmanned areas or areas with high crime rates. If this is a challenge you face, find a generator supplier who can supply secure-containerised generators that are disguised to resemble generic construction containers. These unbranded containers can house a range of generator sizes, their fuel tank and distribution equipment – offering protection from theft and vandalism.
5. Space
Space and access restrictions can be an issue, particularly on small footprint city centre sites. There are a few things to consider if space is a problem you face. When possible, select generator sets with a large capacity integrated fuel tank, which is a major space saver. The size, shape, and footprint of generators variy widely, as does fuel capacity. A large fuel tank will reduce fuel deliveries to site, both minimising transport disruption and reducing the carbon footprint via travel miles. Don’t overlook site access for refuelling. Aggreko offers a fuel management service, to alleviate the hassle of ordering and delivering fuel to ensure continuous power on your site.