Low-Key Hybrid

New Volvo-NTM Joint Venture in Production

A fleet of Volvo/NTM hybrid refuse collection vehicles will start work in Solna, Sweden in January. The contract - which included an environmental 'bonus' clause - was won by Sita Sverige

Next month (January 2012) the Swedish division of waste and recycling contractor, Sita Suez will start a new contract in Solna, a pleasant residential town of 70,000 inhabitants, close to Stockholm. The vehicles used on this contract will be brand new Volvo FE 6x2 rearsteers, fitted with 'KGLS-2B' 16 cubic metre capacity compaction body/hopper units designed and built by NTM. So far, there's nothing dramatically different about this story. Specifying high quality products to do the job in the most cost effective, reliable manner is after all, the Swedish way. It involves planning ahead and whole life cost analysis - sadly not factors always to be found in every commercial waste collection contract.

So what marks this story out as being different? A couple of things. Firstly, this entire new fleet of refuse collection vehicles (RCVs) will be diesel-electric Hybrids - that is to say, once the entire fleet order of six has been delivered, no standard diesel-fuelled chassis will be operated. And secondly? The town council of Solna wants to show 'Big Brother' next door - neighbouring Stockholm city council - how to be at the very forefront of reducing emissions and noise in waste collection operations. Although as I was to discover, this is more out of a desire by Solna Commune to attract more industry and corporate headquarters - and the professionals that work in them - away from central Stockholm, than a simple municipal one-upmanship. In other words, the exercise is seen as an investment in the town infrastructure, designed to make Solna an even nicer place to live and work.

The new NTM hybrid vehicles will work with a two-man crew on domestic wheeled bin collections as detailed above

The method by which these new hybrid vehicles have been deployed may also be of interest to other waste collection policy makers around the world because whatever 'Green Agenda' you support, the simple fact is that specifying Hybrid truck chassis and/or compaction systems is going to cost anything up to 80% more than standard diesel-powered units. To make matters worse - and even more expensive - hybrids can also feature a significantly lower payload or, in other cases, have a shorter operational on-station time due to battery pack range limitations. This makes the 'Green Option' less efficient - adding to the cost-per-tonne of material collected.

Is less more?

Sweden is a very honest country. Swedish taxpayers like to know all the facts, then have an opportunity to vote democratically on the solution. With no hidden secrets. So how did the town council of Solna convince the citizens to fund a brand new fleet of waste collection vehicles that cost substantially more than the standard RCVs currently on the market? The answer is refreshingly up-front: pointing out the added advantages in terms of reduced exhaust emissions and a significant reduction in noise. So 'less' in the context of emissions, can be worth more.

Solna was able to achieve this upgrade in the waste collection service by working with a commercial contractor partner - Sita Suez. As Malin Cronqvist from Sita Sverige explains: "Our contract with Solna runs for nine years, and while the other bidders were at liberty to put forward a price using conventional diesel-powered vehicles, there were what I guess you could call special bonus allowances or 'house points' in the contract for those bidders who were able to provide more environmentally-friendly solutions."

Malin adds that the bidders with the 'greenest' vehicle purchase option (and highest quality operational solutions) would ordinarily be at a major disadvantage, over bidders planning to use cheaper vehicles. To overcome this, the contract had a series of 'environmental bonus' allowances designed to offset a higher initial investment - making it possible that environmentally-friendly bids could still win. The allowances range from $180,000 for a fully electric chassis, down to $50,000 for a biogas-fuelled unit.

A new partner

So with the contract won and the new vehicles ordered, what do the residents of Solna have to look forward to? In an effort to provide the answer, I spent the day with the two-man crew of the first Hybrid RCV to be delivered to Solna. Surprisingly, this is only the second such unit that NTM has constructed. The original prototype built had a NiCad battery pack, but suffered some operational issues regarding range and temperature control of the batteries during the huge seasonal variation in temperatures to be found in Sweden.

Using larger communal 1100 litre containers, as seen here, from apartment blocks. NTM 'Barlift' binlifters have been specified

"We weren't happy with the performance of the battery pack, so we had to find a better solution," explains NTM export manager Anders Hagglund. That 'better solution' was a brand new Lithium-Ion battery pack and battery management system designed and manufactured by NTM's new battery supply partner European Batteries Oy of Tuusula, Finland. The relationship highlights the sensitive issue of 'battery audit'. "We started off designing and manufacturing of battery management systems," explains Hans von Nandelstadh sales manager at European Batteries. "But it was clear that in addition to a requirement to get the most out of any installation, there were issues relating to battery quality and consistency."

The ethical issues relating to the materials used in Lithium-Ion battery production, how those raw materials are obtained and processed and just as importantly, how they are to be disposed of, also have to be addressed by publically-funded organisations such as councils (communes). "At European Batteries, we give our customers a clear paper trail that shows how our raw materials are obtained. To address the quality issues, we decided to manufacture our own battery packs," he adds.

Can you hear it yet?

The last thing an already expensive product needs is more cost. "Yes, it's true our products are more expensive than battery packs sourced from the Far East for example, but we would argue that such costs need to be assessed on a whole life basis," von Nandelstadh explains.

It's true what he says - working closely together, Volvo, NTM and European Batteries have been able to build-in two compartments on either side of the Volvo chassis, without any loss of body length. In fact, were it not for the 'Nyhet Hybrid' logos on the side, the casual observer would be hard-pressed to distinguish this machine from a standard 6x2 rearsteer Volvo chassis with an NTM body. Except for one thing - it's so quiet. Twice over. Firstly, the drivetrain in the Volvo FE chassis is itself a diesel-electric Hybrid - although it is unlikely to be used on the open highway in electric only mode. The battery packs should give enough capacity for the vehicle to operate in shopping precincts or the courtyards of apartment blocks where the exhaust emissions and noise of a diesel engine would be a problem, however. Where the 'automotive' aspect of the hybrid drive really delivers is in 'launch mode' - that is, using the battery power to assist the diesel engine in moving the vehicle away from a standing start.

This extra 'punch' enables a smaller, less powerful diesel engine (compared to a diesel-only truck) to be specified. This might go against the tide in current truck engineering - where large capacity 500 hp engines with flat torque curves are now considered essential to haul 40 to 50 tonnes along the highway, but on an RCV there are more important priorities. The smaller and lighter the drivetrain, the greater the margin for payload. But the key advantage is when an RCV has to stop - and then start again - hundreds of times each working shift. Normally, that puts a massive strain on the drivetrain and braking system. The power needed to drive the hydraulic pump for the compaction system and binlifters can also have a dramatically bad effect on fuel consumption. So the added 'push' from a hybrid electric motor and the capability to capture and re-use energy captured during braking, comes in doubly useful.

Double shifting option?

And the second aspect of the Hybrid package? That's the battery electric power to drive to the hydraulics for the body compaction system and binlifters. Here, an 'all electric' mode of operation with either the truck engine shut down, or on constant tick-over will be the norm. "Our operational trials so far have indicated that we can expect to get up to four truck loads of domestic waste and recycled materials per battery pack charge," Hagglund explains."

NTM has also produced an environmentally-friendly binwash unit in response to a need for greater hygiene as a result of bi-weekly collection from wheeled bins

So is it all worth it? I guess the best people to answer that will be the residents of Solna when the new contract goes 'live' next month. Without the diesel engine revs rising or falling as the hydraulics were being activated - there was the added advantage of the driver being able to hear instructions from the crew on the ground. A useful advantage for health and safety.

But the big bonus has to be to the residents. In other parts of the world, collection crews have been physically attacked by residents angry that the arrival of the RCV has disturbed their sleep. In Solna, I suspect the residents won't even hear the arrival of the hybrid. This brings us to the final key point. If the waste industry is being encouraged to purchase and operate more complex and expensive equipment so that national governments, local town or city councils, or even residents groups can boast about quotas or feel good about their public services being run and managed in a 'green' manner, does it all have to cost the rest of us more money? Why should it?

NTM has recently delivered the first of a new design of recycling collection unit to Swedish contractor SPV. The single compartment 'Uno' features paddle-action compaction system

Until now, that cost penalty would have to be met by a grant, or by increased local taxes. So the availability of an otherwise standard 26 tonne RCV that operationally only has a half tonne payload disadvantage over a standard unit could make a difference. A high quality truck chassis and an equally high quality compaction body unit could work for maybe seven or eight year without need for a major refit. A high quality battery pack that has been designed for over 3000 work cycles and takes into account that Lithium-Ion batteries will lose up to 20% of charge capacity after anything from three to five years is a tougher problem to solve.

European Batteries over-rate the capacity to cover the power loss. The end result is that an NTM Hybrid will cost around 50% more than a standard diesel RCV. But it could do twice the work. How? Because it's quieter, each hybrid could work with two crews over a 24 hour period - starting early in the morning before the downtown area is chocked by traffic congestion, moving to outer suburban districts during the day when people are at work, then back again to collect recyclables from downtown apartment blocks in the late evening. The vehicles in Solna will start at 5am with four loads per 24 hours. Suddenly the more expensive product could be the most cost effective. If that's not exiting enough, Volvo, NTM and European Batteries also have another project in-build - an all-electric 26 tonne gross weight RCV. But that's another story.....

Malcolm Bates is collection and transport correspondent for WMW magazine. email: malcolm@automotivespecialists.co.uk