Hybrid is Not Just for Cars Anymore

All-electric drive proves more efficient, cleaner and quieter, even for screeners and trommels.

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One of the most common questions I am asked is how to save money in some way, shape or fashion. The response I give the most is to automate something, convert to electric, or both. An electric motor doesn't need the air filter blown out every day, or the oil changed, or the radiator checked. You push a button and off it goes.

Komptech is constantly looking for ways to help operators cut their costs. Fuel savings are a big part of that, and more and more of the company's machines are hybrid – they have dual power capability. Komptech hybrid machines feature all-electric drive, with an auxiliary onboard diesel generator with the capability to run directly off the electrical power grid.

The all-electric drive is more efficient, cleaner, and quieter. The generator allows the customer to move from site to site with ground power or not, and the generator is much more fuel efficient, than a diesel over hydraulic units when it does have to be used. With fuel tanks of 60-80 gallons, they only need fueled a couple times a week. Because of the low rpm of the generator, sometimes it's difficult to tell if the machines are running.

Komptech offers hybrid drive in its windsifters, star screens, and trommel screens.

The Komptech Star Screens have been electric powered for a long time. A diesel generator burning about one and a half gallons an hour has been putting 200 yards of finished product on the ground. Since the advent of Tier 3 engines, the addition of a ground power plug was added to most machines. Any site with 480v 3 phase power, can plug directly into the units. Most generators are 40-80kw which means they do not use a whole lot of electrical power so upgrading service is not necessary in most cases.

So what does it save?

In a previous article, Komptech USA writer Ralph Kirschner used this comparison:

  • A Cribus 3800 Trommel Screen running from plug in ground power requires 30 kW to operate. At 9 cents per kilowatt, that's $2.70/hr., x 2000 hours = $5,400 per year.
  • The same machine running from the diesel generator requires 1.5 gal/hr. fuel x $4.00 gallon = $6.00/hr. x 2000 hours = $12,000 per year.
  • Diesel powering an equivalent size hydraulic machine uses approximately 30% more fuel, or 1.95 gal/hr. x $4.00 gallon = $7.80/hr. x 2000 hours = $15,600 per year.

In this case, operators can save over $10,000 per year running on grid power instead of conventional diesel hydraulic, or $3,600 per year running on the diesel generator. Either way, the hybrid machine costs much less to run. In either case, there are no hydraulic lines, pumps or motors to leak, break, or come apart and contaminate the entire system.

The new Cribus line of trommels is now electrically powered. One of the biggest advantages, aside from the electrical savings, is that Komptech has added a load sensor to the hopper. This totally adjustable sensor, allows the trommel and hopper to stop as the hopper empties. This allows the drum to stay full of material and not run empty, contaminating your product with larger pieces that fall through an empty trommel drum. This will make products, especially on the mulch end, much more consistent. Komptech just delivered its first all electric Cribus 5000 Trommel into California. This unit has a 9-yard hopper and 50 square meters of screen area.

With all the stopping/starting, plugging in or not, how are warranty hours tracked? Good question. They are tracked separately. There is an hour meter for the trommel and an hour meter for the generator. This allows for accurate accounting of hours for warranty and servicing.

Times change, and so should your ways. It's those that look ahead that see the change.