Seven steps for improving sustainability with mobile compressors

Compressors traditionally use diesel to power an internal combustion engine. However, this fossil fuel is polluting and the cause of many health problems. Moreover, diesel engines are not very energy efficient: for every Joule of energy input, only 40% is output.

Governments worldwide have recognized the adverse effects of diesel and introduced increasingly stringent regulations to reduce emissions for machinery and road and off-road vehicles. For example, in Europe, the Stage V emissions standards specify a limit for particle number emissions. The norms also stipulate that diesel particulate filters and after-treatment systems are required. If engine-powered compressors are still required on-site, ensure they adhere to the latest regulations. 

Modern machines have been designed with energy efficiency in mind and to optimize fuel consumption. Select equipment that incorporates efficiency features. For example, some compressors include optimizing technology such as an automatic start-stop system (like that available on a car). When there is no air demand, an onboard controller software ensures the engine’s speed is lowered, or even shuts down the engine to save fuel. Whenever air demand is resumed, the engine automatically starts up again so that the operator can continue working seamlessly. 

Look at the engine inside the compressor and consider what fuel it requires. Simply by changing the fuel, some mobile diesel compressors can be turned into carbon-free machines immediately. For example, some Stage V engines are certified to work on biodiesel Hydrotreated Vegetable Oil. This fossil-free fuel is produced from recycled vegetable oils and fats and burns cleaner than regular diesel. 

If the site and the application allow, specify an electric compressor since they deliver the highest efficiency levels (90% of energy at the output shaft) and are the most sustainable option. They are also more compact, silent, and emit little heat. Additionally, running an electric machine is much cheaper than running a diesel one, and the lifetime of an electric motor is much longer. When plugged into the grid, this compressor provides a continuous energy source, and no fuel top-ups are required.

If demand for compressed air fluctuates, a Variable Speed Drive (VSD) compressor can enable construction sites to operate even more efficiently, and therefore, more sustainable. VSD compressors automatically adjust the motor’s operating speed to match the compressed air demand, enabling operators to save further energy and associated costs.

VSD compressors also offer another advantage as operators can future-proof their investment. VSD compressors can be driven by modern batteries or emerging fuel cell technology. 

Where there is no source of electrical power available, battery-driven options should be considered. When air consumption is moderate, and work can be carried out by smaller-sized motors, battery-driven compressors enable operators to work more sustainably. Compressor user data analysis shows that in practice, compressors in construction applications run for only a few hours a day, in variable to low load conditions. In these cases, a small electric compressor can easily be powered by a battery pack throughout the working day.

Furthermore, using battery-driven compressors means contractors can enter bids in low emissions zones or for CO2-neutral infrastructure works that are subsidized by some governments.

With current battery technology, a hybrid approach typically provides the right balance between sustainable and practical. In a hybrid arrangement, an internal combustion engine, electric motors, and/or batteries are combined. They generally operate so that electric compressors connected to the grid, or a battery pack, take the baseload, and diesel compressors are engaged for the top load. An electric compressor is often two times cheaper to run than a diesel unit, so this setup benefits the operator and the environment.

Battery-powered electric compressors are poised to become the first all-in-one hybrid solutions. These compressors would offer the flexibility to work with on-site electricity for peak demands, and while recharging, they switch to battery-powered operation for remote jobs. 

While the world’s leaders have made pledges to reduce carbon emissions, construction companies and those in the supply chain are also setting targets. For example, Atlas Copco’s Portable Air Division aims to be carbon neutral in all its operations by 2030. The division will also reduce the carbon emission from the usage of its products, and it will offer a C02- neutral alternative for every application of its solutions globally.

This is an exciting time for the industry, and there are multiple sustainability gains to be made through specifying the right equipment. Companies that want to get ahead and improve their sustainability can already choose more environmentally friendly options to power their compressors, either with a synthetic, fossil-free fuel or electricity.