Hydrogen fuel cells have been gaining a foothold in materials handling applications and have proven benefits over lead-acid batteries. As with any disruptive technology, the incumbent stakeholders are upset and naysayers will emerge.
A similar disruption to the status quo happened in the materials handling industry with the advent of electric replacing internal combustion forklifts. From lower cost of operation to fewer concerns about direct emissions, electric forklifts provide many advantages. Today, they are an integral part of supply chain systems, and have a higher marketshare growth rate than engine-powered forklifts.
Technology advances have also allowed forklifts to keep up with the demand for higher productivity in distribution centres, allowing for better operator interfaces, increased performance through AC technology, and better integration of the tools of the supply chain such as RF scanning and RFID. The choice of lead-acid batteries for powering electric forklifts has remained unchallenged until now. However, as operations become multiple-shift and the performance demands of forklifts increase, the lead-acid battery is the weakest link in the operation. Long charging times, managing multiple batteries and chargers, and the housekeeping and maintenance associated with battery dependence mitigate against increased productivity.
This table outlines the shortfalls of a lead-acid battery system and the advantages of fuel cell solutions. Hydrogen Fuel Cell Shortcomings?
The shortcomings sometimes attributed to fuel cells include the following: Cost:
Largely due to low manufacturing volumes in the early years of introduction, the acquisition cost of fuel cell power packs and hydrogen refuelling stations is typically higher than for batteries - although much of the increased cost is offset by investment tax credits and additional grant programs administered at the state level for clean energy technologies. Virtually no fuel cell conversion goes forward without being justified economically on a lifecycle cost basis. While there are environmental and public perception benefits to be reaped by early fuel cell adopters, demand for the technology is being driven by the productivity benefits it provides that save money over the life of the equipment. Hydrogen Availability:
The hydrogen refuelling equipment associated with a forklift installation is often assumed to be complicated and expensive - a statement that is largely untrue. A hydrogen refuelling system - including an on-site generator (e.g. a steam methane reformer for converting natural gas to hydrogen), compression, storage, and dispensing - is industrial equipment on par with battery changing and charging systems in terms of capital cost, installation cost, and complexity. A large fleet of forklift trucks using lead-acid batteries requires a substantial amount of indoor space dedicated to storing, charging, exchanging, and maintaining batteries. This space is potentially valuable real estate that is removed from productive use, and is occupied by complicated and expensive equipment, such as multi-tiered racks, battery wash equipment, heavy-lifting equipment, and the associated venting and chemical handling equipment.
A huge advantage of the hydrogen system over battery charging is that nearly all the equipment is located outdoors. Hydrogen dispensers for the forklifts are installed at convenient points throughout the facility, and occupy minimal square footage. Since the fuel cell is not removed from the forklift, there is no need for heavy-lifting equipment or any of the safety concerns associated with battery changing. Valuable indoor space is reclaimed and can contribute to the revenue-generating activities of the operation.Green Technology:
Small-scale hydrogen generators can be installed on-site to provide all the hydrogen needs of a forklift fleet, thereby eliminating the emissions associated with transporting gaseous or liquid hydrogen over the road from remote sites. Such generators are cycled to produce hydrogen on demand and use very little electricity. According to Argonne National Laboratory, hydrogen generated from natural gas on-site has 33% lower greenhouse gas emissions than batteries charged by electricity in the US. According to the authors, "Significant benefits could be obtained by replacement of battery-powered forklifts with those powered by fuel cells using hydrogen from steam-reforming of natural gas" - precisely the solution that has been developed for the materials handling application and is commercially available today.
Fuel cells offer many operational benefits for a multi-shift high productivity forklift fleet and are well positioned as a modern technology to allow the full benefit of today's advanced forklift motors and controls. Practical options exist for clean and economical sources of hydrogen fuel. Most importantly, in many high productivity operations, fuel cells are the technology of choice on a lifecycle cost basis, compared with both conventional and fast-charged batteries. In spite of the skeptics, many companies are blazing a path with fuel cells and are reaping the early benefits.
- Moataz Eldib is director of sales with Nuvera Fuel Cells materials handling line of fuel cell solutions.