On-board charging of forklifts
It is an American tradition to want the newest, fastest, sharpest vehicle. From the first beater we drove in high school to more sophisticated and expensive rides we buy and collect later in life, our fascination with driving endures.
The material handling vehicle market is the first to see a new, clean and cost-effective power source. Carmakers and consumers are only dreaming of the kinds of things that can be done today on a lift truck. Hydrogen fuel cells are promoted as the next big thing for powering vehicles, and some forklifts are using hydrogen fuel cells. But there are still big hurdles to overcome before we see widespread acceptance of hydrogen. High cost, safety concerns, fuel availability and demanding infrastructure requirements all limit the use of hydrogen fuel. The high pressure required for hydrogen make storing and using the fuel complex and potentially dangerous.
However, a new type of fuel cell is available for material handling vehicles that overcomes the obstacles of hydrogen. It is powered by a clean, cost-effective fuel—methanol, a very common chemical used in everything from windshield wiper fluid to clothing fiber, solvents, magnetic film, mattress foam and many other goods. You may even drink it, unknowingly, because there are small amounts of methanol in Coca-Cola. Methanol is the preferred fuel for powering the vehicles at the Indianapolis 500.
Direct Methanol Fuel Cells (DMFCs) are a clean and cost-effective technology for material handling vehicles. They work with any vehicle and any battery. Fleet managers seeking to reduce greenhouse gas emissions are using DMFCs to trickle-charge the batteries in forklifts, tuggers, pallet jacks and automated guided vehicles. This approach is called on-board charging. It charges lead-acid batteries while they operate.
Saving Money with On-Board Charging
Lift truck operators spend a significant part of their day keeping their vehicles charged and running. The amount of time varies by organization and includes (a) the time required changing the vehicle’s batteries, (b) the time spent driving to and from battery changing stations and (c) the downtime other workers experience when the lift truck is unavailable. Over two eight-hour shifts, estimates of labor lost to swapping and charging range from 30 to 80 minutes. On-board charging reduces this productivity loss to less than five minutes over the same two-shift period.
DMFCs continuously charge the vehicle battery even as it operates, completely eliminating the time required to stop and charge batteries. On-board charging provides an extra 15 to 40 minutes per shift when battery changing is eliminated. This results in greater output per worker and, ultimately, lowered labor costs.
A second factor plays a role in the productivity improvements available with on-board charging. As batteries drain during a shift, their output power decreases. This reduces vehicle performance and, therefore, worker productivity. The productivity loss is even worse as batteries age because they then require more frequent charging. In contrast, DMFCs maintain a constant state of battery charge and enable the vehicle to continuously operate at peak power.
Using DMFCs, managers require fewer lead-acid batteries to run their fleets. Traditional operations require two or three batteries to support two-shift operations. Only one battery per vehicle is required with on-board charging. This cuts battery requirements by one-half to two-thirds.
On-board charging improves lead-acid battery life. Charging from the grid causes the batteries to get very hot. Over time, heating shortens battery life. However, batteries never get hot when continuously trickle-charged with an on-board charger. Using on-board charging results in a substantial reduction in battery cost from fewer battery purchases and increased battery life.
It also eliminates the need for external battery charging. This eliminates the need to dedicate space for battery charging and battery storage. Valuable cubic footage on prime facility real estate can be returned to productive use.
Benefits for Dealers
On-board charging also brings benefits to material handling dealers. First, DMFCs operate with all batteries and vehicles. Any electric vehicle can be equipped with an on-board charger and existing vehicles can be retrofitted with them as well. Secondly, no special infrastructure is required to sell and service DMFCs. Regular methanol delivery can be arranged for any location in all 50 states. DMFCs can be installed and serviced with any dealership’s existing tools, personnel and facilities. Third, there are no special safety requirements to work with methanol. Every local fire department has simple, straightforward permits for its use. Many vendors use methanol right in their booths at large trade shows, unlike hydrogen, which cannot be displayed in such a manner. Finally, with just two days of training, a technician can be fully trained on the installation and support of a methanol fuel cell, so your existing personnel can generate additional service revenue.
The financial benefits of on-board charging are significant. Calculating the payback that on-board charging can deliver to your customers is simple. Results from data across a number of industries show that per-vehicle savings can range from a few thousand to tens of thousands of dollars annually. Most organizations see payback on their investment before the end of their second year of operation.
Reducing Greenhouse Gases
On-board charging is a green technology. This is an important selling feature for end-users. Methanol fuel cells reduce greenhouse gas emissions from material handling vehicle fleets. Roughly 85 percent of the electricity generated in the United States comes from coal-fired power plants. Methanol fuel cells emit no particulates, NOx, SOx or CO. DMFCs for on-board charging may reduce CO2 emissions by approximately 30 percent when compared to charging batteries with electricity supplied from coal-fired power plants on the grid.
Calculating the reduction in greenhouse gases is an interesting topic. Emissions generated from fuel use are only one part in the total emission cycle that begins with extraction and continues through processing, transportation and use. Accounting for all these stages in a fuel’s life cycle gives a full picture of total greenhouse gas emissions.
Well-to-wheel analysis is a method of understanding the emissions profile of a fuel-technology combination. Hydrogen fuel cells release no CO2 when they are used. However, this is an incomplete picture of their emissions profile because CO2 is emitted in the process of creating hydrogen.
Table A shows that methanol reduced CO2 emissions by 41.7 percent, or almost three times the reduction in emissions compared to hydrogen, according to a study done in 2000 by (S&T)2 Consultants. It demonstrates that methanol yields the greatest overall reduction in emissions when the full fuel cycle from extraction through refining, delivery and use is considered. The metric used for measuring the overall pollution of fuels in this study was grams of CO2 per mile driven. For gasoline, the figure is 500 grams of CO2 per mile. Compressed hydrogen reduces this 500-gram figure by 13.8 percent and methanol reduces it by 41.7 percent.
Direct methanol fuel cells used for on-board charging are an important new technology for material handling dealers. They help customers increase vehicle utilization, lower costs, right-size fleets, increase worker productivity and reduce greenhouse gas emissions. Productivity gains are considerable. Twenty to thirty minutes per eight-hour shift can change non-productive use—battery swapping—into productive work. The methanol distribution infrastructure exists today. Methanol is simple and inexpensive to support and provides you with a valuable new technology for your customers.
Outfitting material handling vehicles with DMFCs may not be as exciting as cruising in a ’67 Mustang with the top down on a summer day, but it will help your bottom line while you get the satisfaction of doing something to improve the environment.
|Meet the Author
Mannix O’Connor is director of marketing for Oorja Protonics, a manufacturer of methanol fuel cells for material handling vehicles located in Fremont, California, and on the Web at www.oorjaprotonics.com.