Cut energy consumption and costs without compromising your operation
Manufacturers can cut their energy consumption—and costs—on the shop floor without compromising operations, but they need to start thinking differently, and to look beyond the obvious to truly understand how they use electricity. The first place to start is with your hydro bill.
“When we first start talking with people, we want them to understand their electricity bill,” says Ralph Williams, energy services supervisor at Hydro One in Brampton, ON. “Having knowledge on how to use electricity is paramount before you start to put a conservation plan together.”
The low hanging fruit—HVAC efficiencies and basic HR practices—can be understood and, hopefully, addressed quite easily. But manufacturers have some unique requirements.
“Most metal manufacturers have interval meters,” says Williams. “They can find out what they are using every hour of the day. Then they can break it down: this much for compressed air, this much for production, this much for office, etc.”
With a 24 hour view of electricity demand, manufacturers can then work to spread the demand off of peak hours. But what if operations are continuous and peak hours are, essentially, all the time? Then you have to calculate the “power factor” of your machines. The power factor is the ratio of real power, or capacity, to apparent power, which is the current and voltage on the circuit.
“If your power factor is below 90 per cent, then you are incurring a surcharge,” says Williams. “If you take a typical motor, most are over-sized. So, the job may take 20 horsepower, but you use 50 horsepower.”
Many manufacturing environments are running at a power factor below 90 per cent, for the simple reason that motors are always overbuilt. They have to be to get the job done. How then can you adjust your power capacity to make things as efficient as possible, while ensuring that you still have enough power?
“Power factor correction capacitors can help, and a lot of companies already have them in place,” says Williams.
In fact, Williams says that the power factor issue is a fairly straightforward fix, but it requires the right people to check, assess, and suggest a solution. And this is not something that should then be left for many years before re-visiting the issue.
“You might have new equipment, an added load, but haven’t added the correction; you need to keep adjusting power factors,” says Williams. “The number of people that are still paying a surcharge is sizeable.”
Help is on the way
Utility companies can help manufacturers reduce their energy consumption, but so can consultants such as 360 Energy Inc., a firm that provides energy management programs and energy saving initiatives through its head office in Burlington, ON.
“We began as an energy management company and expanded into energy consulting,” explains Dipal Patel, a project manager at 360 Energy.
The company has an impressive track record, having helped AcelorMittal Woodstock, which is involved in the processing, finishing and distribution of steel, to save 500 kw over a typical weekend. By identifying and turning down 83 redundant items in AcelorMittal’s plant, it reduced the base load by 20 per cent.
“We get people in all departments—finance, operations, engineering, maintenance—and we put them on a team,” says Patel. “If they spend 10 to 20 minutes a day, by the end of the year they have put a lot of time into energy management.”
This solves a problem that is often overlooked: the people who are in charge of energy use are separated from the people who are in charge of energy costs. By bringing them together an organization can develop an understanding of what can be accomplished in-house, what might require outside expertise, and which options would be capital intensive.
“It can be complicated,” says Fred Granek, vice president of sustainability and executive director at the Canadian Centre for Pollution Prevention (C2P2). “This is because a lot of energy issues are about process improvements.”
Granek says that C2P2, which works on comprehensive pollution reduction strategies, will fit energy conservation into a larger environmental plan. Usually, HVAC and lighting are the places to start, but after that it becomes a challenge.
“The processes can be complex,” he says. “Even with ventilation it isn’t necessarily obvious. When you look at a 30-ft ceiling most of the fans are undersized, they just stir air up there, but bigger fans save money and work.”
Compressors are another area where plants can do a lot to save energy. Ralph Williams from Hydro One notes that about 70 per cent of all manufacturing facilities have compressed air systems. This is one of the most expensive uses of energy: to generate one horsepower of compressed air requires eight horsepower. As well, typical air leaks in compressed air systems account for up to 30 per cent of the compressor’s output.
“You walk around a plant and you can hear compressors leaking,” says Williams. “That’s just energy being blown out to the atmosphere. A lot of people complain about having to get bigger compressors, but really they should be addressing the leaks.”
Building a culture of energy conservation is something that utilities and consultants can help with, but the willingness has to be there on the part of management. There is perhaps no better example of this than Jim Ecclestone, president of Calstone Inc., a steel furniture manufacturer in Scarborough, ON.
“We can reuse 80 per cent of what we produce,” says Ecclestone. “That’s less energy than would otherwise go to recycling.”
Mr. Ecclestone is nothing if not resourceful. He has built a culture of conversation in his family-run business that has gone way beyond putting in energy efficient light bulbs.
“We have a huge, 2,000 gallon water tank that’s filled with rain water. We flush our toilets with it, and use it to cool our spot welders. Now, those tanks get up to 40º; we’ve hooked up a heat exchanger and fire that heat back into the plant.”
This is a remarkable story of innovation and creative thinking, something that any plant could experiment with—assuming management is behind a culture of energy conservation. It also helps that manufacturing plants have ready access to the expertise needed to make a difference.
“We are building two more heat exchangers,” says Ecclestone. “We use car radiators and build the casings ourselves; we expect that, other than the front office, we will be able to eliminate the need for natural gas.”
And Ecclestone can do this with limited capital outlay.
“A car radiator is a couple hundred dollars, and with the fan I can build a heat exchanger for under five hundred dollars. This isn’t a huge amount of money, and it makes a difference.”
Ecclestone is ambitious, and has become something of a cause celebre within the green manufacturing community. Part of this is because Calstone is not a large company; many consultants tend to focus on bigger organizations, where the economies of scale bring about more impressive savings.
“Our welders are all electrical. We want to reduce our need for energy, our overall cost of electricity, and to reduce our footprint,” says Ecclestone. “I want to be at zero emissions within the next ten years.”
For Ecclestone, that means converting his whole operation to electricity. To make this happen he is relying on Bullfrog power, a “100 per cent green electricity provider.” As power is drawn from the grid, Bullfrog’s generators inject the matching amount of renewable electricity.
“We also hope to have solar powers, as well as more skylights and by the end of the day we will only need about one third of our present lighting.”
Ecclestone’s do-it-yourself approach is a great example for other small manufacturers, many of whom are fighting their way out of the recession and can’t afford the capital intensive outlays that many green initiatives require.
“I could go out and spend a million dollars, but who has that kind of money?” CM
Tim Wilson is a freelance writer based in Peterborough, ON.