Battery powered mowers - A thing of the future?

There is nothing more quintessentially British than the sound of a mower on a sunny spring or summer day, and the smell of freshly cut grass that goes with it. It conjures up images of village cricket matches, lazy days and generally nice things locked away in the recesses of our mind.

---

In today's world, even that simple noise can have its own issues. How noisy actually is that mower, and is it just the aroma of freshly mown grass or is there, potentially, more dangerous carcinogenic fumes emanating from a diesel engine?

Never before has the grounds maintenance industry had such a variety of equipment available to it. There are machines for almost every task imaginable but, in some ways, the choice is more difficult than ever before.

Sometimes, it is even the ability to actually complete the job in hand that is of secondary importance to the box ticking process that needs to be undertaken in order to ensure that the machine complies with policy, health and safety, the environment and so on.

So it is important to ensure that, with any new machine, you have a demonstration and try it out on the job you actually need it to do. Where possible, also conduct vibration testing at the same time. There are so many cases where a machine has been tested for hand-arm vibration (HAV) or whole body vibration (WBV) in a factory environment but, when it is actually at work, the figures bear no relation to those quoted. You only have to look at the recent VW emissions scandal to understand what can be achieved in a factory!
Probably the biggest factor in any machine is the power unit driving it. Not only do you have to look at the merits of different engine manufacturers, but now, more than ever, the actual power source. Do you need petrol, diesel or perhaps even battery power? Each has its own advantages and disadvantages often in equal measure.

2 and 4-stroke petrol engines are still the industry standard. They are relatively simple to maintain, quite clean and offer an abundance of power although, in these environmentally sensitive times, it is still a fossil fuel. Furthermore, look at the cost of the fuel, or the constant trips to refill, or the mixing or carrying of fuel on a vehicle, especially when working in a school or public place. There is also the problem of security. How much petrol is lost in a year, throughout the industry, through fuel disappearing into domestic mowers, motor bikes or even private cars? It's probably something that we would never dream of our employees doing, but it does happen.

Diesel tends to be more efficient, with better torque figures than petrol engines, and is easier to store and maintain. However, we move more into the world of vibrations, noise and we are back to carcinogenic fumes. Also, the weight of the machines can be a problem.

Battery power is the third and most recent option and is the one that, at present, is evolving the fastest. A few years ago, battery power for hand-held equipment was in its infancy for commercial applications and 2-stroke petrol was still the only option. However, most users now have at least looked at Lithium-Ion powered machines with up to 50V, durability, and run times are increasing all of the time.

This has been all well and good for the smaller end or hand-held market but, until now, there hasn't really been an option for electric power in the larger end commercial environment. However, a range mowers from the USA (Mean Green Mowers) has brought a new option to the table.

Whilst battery run times have evolved for hand-held equipment, the operator still has to manage the weight and size of the battery as, invariably, they have to be carried or worn in a harness, whereas a large self-propelled or ride-on mowers can do that for them. Therefore, size and weight is less of an issue. This allows more cells to be linked together and, therefore, an eight hour working day is achievable.

Whilst it will be some time before sales of electric powered mowers rival that of the petrol or diesel alternatives, it is very easy to see some of the advantages that a battery powered machine can bring. Less vibrations, lower maintenance and no fuel costs are huge factors to anyone specifying a new machine and, whilst there are some very sophisticated systems on most modern petrol and diesel mowers now to combat this, the removal of an internal combustion engine takes away the majority of the root cause of vibration.

I have already touched on the noise factor. We've all heard mowers at work and, for many, it is just a fact of life. However, when a school, hospital, office complex or industrial park customer requires all mowing to be carried out before 8.30am or after 5.30pm to minimise disruption, then how can a contractor manage that? Not all areas can be covered at weekends, whilst school exam time often coincides with the fastest growing times in May and June.

Admittedly, a battery powered mower makes a noise when cutting grass but it is far less obtrusive than the diesel or petrol alternative. Similarly, the last thing anyone needs to hear at a crematorium is the noise of a mower revving up and competing with the service, but the grass still needs cutting and maintaining. Whilst most crematoriums will actively try and avoid cutting when services are happening, it is not always possible in the height of the growing season.

A huge factor in the procurement of grounds maintenance equipment has always been back up and service. It is no good whatsoever if the best cutting mower on the fleet spends three days a week in the workshop or if all the sophisticated anti-vibration rubber bushes have perished or split. What is often a simple case of replacing a belt can lead to several days of downtime as the mower has to be removed from site to the workshops, cleaned and then problem diagnosed, then a new belt ordered only to find they are on back order and will be in a week next Tuesday! We've all been there and these scenarios do happen.

This is where an uncomplicated system has the advantage, with the battery powered system there are no belts, hydraulics or engine, and one outstanding feature is that the machines do not allow abuse or mistreatment. If the grass is too thick and heavy, or they encounter an obstacle, the blades will simply disengage, so the problems of burning belts out etc. is completely removed.

The last real factor to be considered in the purchasing process is fuel storage itself. If a mower can hold 10 litres of petrol, and that is enough for the day, then fill it up in the morning and away you go. However, what if you need more fuel to complete the day's tasks? Then you'll need to look at carrying the fuel with you or, alternatively, load the machine back onto the trailer and take it back to refuel, which may incur a lengthy trip.

In an ideal world, you would simply carry a fuel can on the vehicle and top up when necessary but, in today's world, how safe is that? You may fall victim to an opportunist thief or, worse still, come back to a burning vehicle!

The time taken to produce risk assessments alone is quite considerable and, in some cases, spare fuel is not permitted on site. This gives the electric powered option an advantage as you are carrying the fuel with you in a safe and secure way in the form of a battery. Mind you, that is no good if the operator has neglected to plug the machine in the night before! There may even be a benefit from a saving in insurance premiums if fuel is not being carried in removable cans.

Taking into consideration operator comfort, ergonomic controls and even the colour of the paint, it will generally come down to the most important factor, the bottom line! This is where the petrol machine will usually score best as it is the least expensive to buy, with plenty of options available. However, it should not be as straightforward as that. Look at the cost of actual ownership. How much is that mower costing week in week out? Take everything into account, from fuel costs to servicing costs to downtime.

A dealer was recently selling a customer a battery powered chainsaw minus the battery. Once a price had been agreed, he then went on to sell the customer the battery, but the customer thought the battery should have been included in the price! The dealer responded by saying that, if you were to buy a standard petrol chainsaw, would you expect to buy all of the fuel that the machine will use over the next two years in one go as an up-front cost because, if so, let me look at the prices again? This is a very fair point.

The larger commercial battery powered mowers are undoubtedly more expensive to buy at the point of sale, however, the cost of ownership will be less than with a petrol or diesel equivalent when fuel, servicing and everything else has been taken into consideration.

In conclusion, the only certain fact is that there are more options available for the grounds maintenance market than ever before and, in essence, it very much depends on the primary function you, as the specifying customer need the mower to do as to which machine you buy. It is just a question of prioritising what you need and if there is anything you can do to lift you ahead of the competition, keep your workforce happy and safe, reduce your carbon footprint and reduce the disruption essential grounds maintenance causes to the wider picture.

Petrol, diesel or battery? The choice is yours, but at least, there is a viable third option now.

Stuart Rose, Sales Manager, Overton UK
www.overton-uk.co.uk