## Balqon Begins Production of Electric Port Drayage Trucks for San Pedro Ports

##### 25 February 2009
 Balqon E30 rolls off the line. Click to enlarge.

Balqon Corp. has begun production of all-electric, heavy-duty drayage trucks capable of hauling 30-ton shipping containers in and around the San Pedro Bay, California port complex. (Earlier post.)

An initiative of the Port of Los Angeles’s Clean Air Action Plan, the development and demonstration of the Balqon Nautilus E30 electric truck was co-funded by the Port and South Coast Air Quality Management District (SCAQMD) at a total cost of $527,000. Designed specifically for short-haul or drayage operations, this heavy-duty truck can pull a 60,000-pound cargo container at a top speed of 40 mph, and has a range between 30 to 60 miles per battery charge. The Nautilus E30 uses a 336V traction battery pack comprising flooded, deep cycle lead acid batteries with a square tubular positive plate design for maximum exposure to the electrolyte. Features of the pack include an automatic watering system controlled with a proprietary on-board timer circuit; forced air cooling during driving and discharging cycles; and automatic low voltage shutdown during operations. A battery management system monitors each battery cell. Total capacity of the pack at full charge is 160 kWh. The E30 consumes 1.2 kWh per hour of idle operation; 2.4 kWh per mile driven unloaded; and 4.4 kWh per mile driven with full load. An 80 kW battery charger can charge up to four electric trucks simultaneously and can also provide up to 60% of the charge in one hour to meet peak demands during daily operations. Maximum output at each charge port is 40 kW. A charge from 80% depth of discharge takes 3.5 hours with 480 VAC, 3 phase input voltage. The charger uses a priority smart charge algorithm based on vehicle state of charge. The E30 uses a 100 hp (75 kW) continuous rated 230 volt AC vector duty electric motor connected to a flux vector variable frequency controller. Following the successful completion of cargo terminal tests during 2008 of the demonstration Balqon truck, the Los Angeles Harbor Commission approved the purchase of 20 production, electric trucks from the manufacturer as part of the “green terminal” program. These trucks will be deployed as a zero emissions alternative to fossil fuel-powered yard tractors, or “hostlers.” Currently, fleets of thousands of hostlers—which are mostly diesel vehicles and a small number of Liquefied Natural Gas test units—move thousands of containers a day between the Port’s docks and terminal backland. These could eventually be replaced by electric vehicles. The green terminal program will also include the production of five on-road electric trucks. Balqon will work with the Port and Department of Transportation to obtain the appropriate certification for on-road use. In total, the Port is investing more than$5.6 million to demonstrate the viability of electric drayage trucks.

As a partial consideration of the Port providing the first sizeable production order with Balqon, the company will provide a royalty payment to the Port for each vehicle it sells or leases worldwide.

On a kilowatt hour of energy cost-basis, this electric truck costs roughly 20 cents a mile to operate. On a per-mile cost-basis, a common diesel truck could cost anywhere from four to nine times as much, depending on fluctuating fuel costs and actual duty-cycle activity (100% duty cycle equals zero percent truck idling).

On an annual basis, more than two million truck drayage trips take place between the Port of Los Angeles terminals and rail and warehouse facilities within five to ten miles of San Pedro Bay.

An overall calculation of net emissions reductions still needs to be performed to take into account the emissions created in the generation of electric power used to charge the truck’s batteries. However, based on the average emissions generated by the existing fleet of drayage trucks that serve the San Pedro Bay ports, Port of Los Angeles staff estimated the average pollution discharge generated by the estimated 1.2 million truck trips that occurred in 2006 between the ports and a local near-dock railyard (the Intermodal Container Transfer Facility or ICTF).

If those 1.2 million truck trips were to be made with zero emission electric trucks, an estimated 35,605.6 tons of tailpipe emissions would be eliminated, including: 21.8 tons per year of diesel particulate matter (PM), 427.7 tons per year of localized NOx (NOx) emissions, 168.5 tons per year of carbon monoxide (CO), and 34,987.6 tons per year of carbon dioxide (CO2).

There is something fishy with the math around the energy usage when loaded.

The article says the truck uses 4.4 KWHr per mile when fully loaded and can do this at 40 MPH. 40 MPH x 4.4 KWHr per mile = 176KW, yet the truck only has a 75 KW motor.

Either the truck can't go 40 MPH when fully loaded or the motor is making more than 75KW or its very inefficient.

4.4 KWHr per mile seems really high to me, unless that is the energy input to the truck itself and the inverter, motor and charger systems are really inefficient.

me: There are a couple things you're ignoring. One is that the 75 kW is a continuous rating, which is limited by the ability of the power electronics and the motor to dissipate heat. Instantaneously the drivetrain can probably put out double that amount... the peak output is limited by either the size of the power electronics or the power output limit of the battery pack.

But even more important than that is that the 4.4 kWh/mile is an average, probably over a normal daily duty cycle (or some other 'standardized' duty cycle). It is not an instantaneous rating. Pulling a 60 ton load at any constant speed would probably draw comparatively little power, but accelerating one would draw much more than 4.4 kWh/mile.

me: they are using a 5-speed automatic transmission with the electric motor. I suspect the battery to wheel efficiency is rather low. But perhaps a number is wrong.

Notice this: "The E30 consumes 1.2 kWh per hour of idle operation". Why would an Electric use 1.2kWh when idle?

I suppose knowing that answer is why some people get the big bucks.

Two figures are mentioned: $527K and$5.6M. It isn't clear what each covers.

That made me suspect that a lot more money has, or will be spent, before these trucks are fully operational at the port.

Then I noticed they are using lead acid batteries. So perhaps this is not very innovative at all.

Battery recharge time would normally limit use to a few hours a day, but the company web site says their battery packs can be switched quickly so the trucks can achieve a high utilization rate.

We're not told where these energy figures are measured.  Flooded lead-acid batteries are on the order of 70% efficient, so the actual energy input to the motor may be around 3 kWh/mile.

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