Trying to sort through the competing claims of forklift motive power providers is like a Sisyphean task. Just when one is near the end of the decision route along comes new technical improvements or technologies that upset the equation. LPG protagonists, for example, have long extolled the virtues of their fuel over diesel, often cast as the dirty villain of the peace regarding environmental issues and their direct impact on health. But the advent of Stage IV/Tier 4 emissions control directive has greatly improved diesel’s environmental credentials as well as truck economics. This has even prompted Paul Watson, general manager of Doosan Industrial Vehicle UK, which uses LPG and diesel, to proclaim: “The LPG market is decreasing globally as people switch to either cleaner diesel or electric power.” Looking to the future, Wasson says: “We can see huge changes ahead as forklift engine technology is refined and advanced to continue to improve fuel consumption, reduce emission levels and further improve reliability.” A bullish claim, it seems, but unless diesel manufacturers devise an engine that eliminates sub 2.5 micron particulates, a well-known killer of growing concern, then diesel will have an uphill struggle against electric and other, much cleaner technologies now reaching critical mass. Moreover, natural gas usage for vehicles is forecast to cost less than half diesel costs within the next three years.
Another view of near future developments comes from Sany Europe’s chief engineer for port equipment. He says: “It is difficult to look too far ahead, but we are thinking that more hybrid technologies will be developed, and this will probably be because the cost of components will fall.” The question is, however, will these price falls be enough to counter the higher costs of maintaining two drive systems in one truck? With greater certainty he adds: “What I can tell you is that in the next four to five years diesel engines will evolve again thanks to the improvements that are still possible with injection systems.”
So it would seem diesel has some future but what of the threat from newer technologies and developments in electric trucks which now gives them a performance equal to diesel, in the previous absence of which electric was at a significant disadvantage to diesel?
Crown Equipment’s vice president of engineering, Lew Manci, sees a growing trend towards lithium-ion batteries and hydrogen cells. Those large American adopters of government-sponsored hydrogen fuel cell trials are now moving over to full-site conversions, attracted by the solution to issues inherent with lead-acid batteries and an incomparably healthier, cleaner operation compared with diesel. Even the generation of hydrogen need not be an environmental issue because hydrogen can be made from solar electrolysis, as is already happening in one UK car plant. The fuel cell problem, however, is in the initial cost, considerably more than for lead-acid, but some believe it is already possible to achieve a 12-month payback on hydrogen based on large fleets in multi-shift operations, and there is no reason to suspect that initial purchase prices will not fall.
Lithium-ion and its more recent challenger, iron-phosphate powered electric trucks, seem to be gaining traction. The former can be opportunity charged during breaks without adversely affecting battery life, can be charged much more quickly than lead-acid and have much longer run times. Moreover, they do not emit gas during charging and don’t need special battery rooms. Although up to 3 times more costly than lead-acid, lithium-ion prices can be expected to fall. The newcomer to the European market from China, BYD, meanwhile, plans to cut a dash with its promotion of lithium-iron phosphate batteries accompanied with side charging and a quick charge charger. One distinctive advantage is that only 2% is lost in heat when charging, allowing for 98% energy efficiency. With lead-acid batteries that energy efficiency often drops to only 30%.
The future may be green, but it is also challenging and the competing proponents of motive power will fight hard to maintain market share but the good news is that truck buyers and workers will be the winners.