How the right lubricants save energy and how to measure effectiveness

As energy costs continue to rise, energy consumption becomes a greater and more immediate concern to every company’s profitability. Electric motors power most plant machinery and energy costs are often the largest expense of operating rotating equipment.

Operational improvements, such as using the right lubricant, can reduce energy consumption and create significant cost savings. But which lubricants are energy efficient? And how can you measure the impact of energy-efficient lubricants on energy savings

Choosing the right lubricant can reduce costs

A machine uses energy to both move and function, as well as overcome friction. The greater the amount of friction, the more energy required by the machine, which has a direct impact on power supply and costs.
Energy efficiency can be gained by reducing friction, and one of the best ways to do that is to employ good lubrication practices. This includes the use of high-performance lubricants, which help alleviate causes of friction such as carbon deposits, sludge and varnish residue.

Mineral oil versus synthetic lubricants

Mineral oils exhibit poor viscosity versus temperature behavior and low resistance to oxidation. At high operating temperatures viscosity drops significantly causing oil degradation and premature wear of equipment by allowing metal-to-metal friction. Mineral oil degradation is a major cause of varnish and sludge deposits both of which affect equipment efficiency.

In comparison, synthetic oils offer much better viscosity and stability at high temperatures as well as good thermal oxidation, lubricity, detergency properties and film strength. By reducing friction at moving surfaces, synthetic lubricants can help improve machine efficiency and in turn reduce the amount of electricity required to drive equipment such as gearboxes, compressors and pumps.

Synthetic oils also perform well at low temperatures so in regions which have cold winters, there is another direct energy saving to be gained from synthetic oils. Mineral oils often need to be pre-heated during winter as below 10 degrees celsius they start to thicken due to their high pour point - a heating requirement that consumes additional energy. Synthetic lubricants however are, in the main, suitable for operating temperatures up to -30°C and do not need to be preheated.

How to measure the savings

Once a lubricant has been upgraded or changed in equipment, energy savings can be measured by comparing the following:

● Production output - improved equipment efficiency due to better lubrication
● Temperature change - a reduction in the operating temperature range will reduce energy consumption
● Electrical consumption - reduction in electric energy for an electric motor or gearbox
● Fuel consumption

For an accurate and fair comparison the following conditions must remain consistent:

● Equipment must operate at equal capacity when readings are taken
● Use a comparable amount of lubricant
● Measure the equipment in identical operating conditions (load and speed)
● Maintain similar ambient or room temperatures.
● Use the same instruments and methods to measure the energy consumption for both lubricants.
To allow for variables a large sample size is recommended.

In conclusion
High quality lubricants may be more expensive to buy, and the savings can not be realised prior to purchasing and usage. However, the higher cost can be justified by enhanced overall equipment efficiency and a reduction in the total cost of ownership.
Importantly, switching to a high performance synthetic lubricant is more sustainable - less energy consumption, less CO2 emissions and less oil disposal due to longer intervals - helping you to lessen your environmental impact.