Great energy savings to be made from more efficient motor control
Motor driven systems today stand for two thirds of the Swedish industry’s electricity consumption. Variable speed drives controlling electrical motors across the world have saved Euro 8-10 billions. Yet they only represent five percent of the existing motors. Thus great savings can be made by increasing efficiency, in money as well as in environmental impact.
Photo: Hydro Polymers in Stenungsund, Sweden, produces the plastic material PVC. Emotron variable speed drives are used to control chimney fans, pumps, compressors, mills and centrifuges. Martin Ljungqvist is foreman at the electrician’s department: “Reduced energy consumption and equipment wear are the main advantages.” Photographer: Bo Kagerud, Sweden
Electrical energy is a global scarcity
In Sweden, as in most countries, electrical energy is an expensive scarcity constantly under debate. Hydro electric, nuclear or coal power – the methods of producing electricity may vary, but one thing is certain; the price will be high, not only monetarily but also in terms of how it effects society in general and the environment in particular.
Every effort is made to find alternative energy sources, ensure access to electrical energy and minimize environmental impact. Hydro and solar energy is extracted, new fuel sources developed and research conducted on different levels to find new ways of securing energy supply in the future.
Energy policy must strive, in short and long terms, to secure supply of competitive and environmentally friendly electrical energy, as well as to find ways of optimizing energy consumption.
The right measures can halve the energy needed
Through information, directives and education, Sweden and other countries could start making considerable energy savings right now. Well-tried technology is already available that could halve energy consumption in a number of applications and processes.
A good international example is the EU project “Motor Challenge Programme”, which aims to increase the efficiency of systems driven by electrical motors. Energy surveys show that motors and motor driven systems stand for two thirds of the industry’s electricity consumption and 30 percent of the energy used in the EU.
Fan operation consumes 10 TWh in Sweden only
A US survey of 1994 showed that electrical motors in industry processes consumed approximately 25 percent of the energy used. This makes electrical motors in industrial usage the largest electricity consumer in the US.
The most common applications are fans, pumps and compressors. In Sweden, industrial fan operation alone consumed approximately 10 TWh in 2002. This corresponds to the yearly production of one and a half normally sized nuclear power plants.
Savings by analyzing energy consumption
Considering the fact that the efficiency of fans, pumps and compressors can be increased by 30-50 percent, it is obvious the industry can save a lot of money. The basic industry of Sweden, consisting of about 200 companies, stands for approximately 80 percent of energy consumption and of course has the greatest saving potential.
However, small companies and municipalities can also make considerable savings by analyzing their energy consumption. Imagine all the pumps used in pump stations, water purification plants and sewage treatment works, where investing in more efficient motor control would soon pay off.
Efficient and reliable technology
But how do we define optimized energy consumption? Increased efficiency, reduced energy consumption, minimized environmental impact? What technology and what products could and should be used?
Naturally, everyone must carry out an energy analysis to find their actual need and their possibilities to reduce consumption.
When it comes to motor control, there are efficient and well-tried products. Variable speed drives, soft starters, load monitors and control systems can contribute to energy savings and reduced environmental impact, and thereby reduced costs for the user.
Variable speed drives installed across the world today are calculated to have saved the yearly production of 20-25 power plants, equivalent to Euro 8-10 billions. And still, only about 5 percent of the world’s electrical motors are controlled by variable speed drives. This means there is great potential for energy and cost savings.
Swedish company focused on energy savings
The Swedish company Emotron AB focuses on developing, producing and marketing products that ensure an economic and reliable operation of electrical motors. The company has achieved cutting edge knowledge in starting, protecting, controlling and stopping machines and processes driven by electrical motors.
The company focuses on applications such as pumps, fans and compressors. Product development is based on a wide experience from processes driven by electrical motors, combined with deep knowledge in power electronics. The goal is to offer products that not only save energy, but also reduce installation and maintenance costs.
Investment that soon pays off
Increasing energy costs and low prices on products such as variable speed drives combine to make more efficient motor control an investment that soon pays off. With today’s access to competent energy consultants and reliable products, only the will to save money and energy sets the limits.
By Bo Andersson, Emotron AB, Sweden