The Electric Bike Commuter Option

After moving into a house near the top of Mt Nelson, I found the number of days I was cycling to work dwindling from 4 or 5 days a week down to just one or two.  This was especially true in the colder winter months when the thought of slowly clambering up the Mt Nelson bends through the cold rain and wind after work too often lead to me walking out the door and jumping into my car, not onto my bike.

However, I’d been increasingly thinking about alternative commuter options, and what sprang to mind was an electric bike, so I took the plunge and bought a conversion kit in 2010 to give it a try.

I’ve now been riding it for a few years, and thought I’d share what I’ve learnt for anyone else who has considered this as a commuter option, or even just wondered about the small number of electric bikes out on our roads.

To give this discussion some context, I decided to compare my ebike against the other obvious options for getting to work ... a car, a bus, a normal bike and walking.  It's also worth noting that my commute is about 8kms each way (depending on the route) but is mainly downhill on the way to work, and mainly uphill (300 metres climb) on the way home.

The Electric Bike

Electric bikes are really advancing in terms of choice, and I won’t even begin to try and deal with those in this article (If you're interested Ride On Magazine has a good review of electric bikes in their June-July 2013 Magazine or pop in and see Ahmet and his crew at ecobikes at 100 Elizabeth Street).  Suffice to say that after a bit of research on the net, I decided to buy a front wheel conversion kit from a company called Solarbike (www.solarbike.com.au). 

The main attraction for me of this particular kit was that I had a spare mountain bike sitting in my garage and because this was a front wheel conversion drive, it looked easy to install and I thought keeping my existing shimano XT gearing on the back would mean I still had lots of gears to play with if I needed them (turns out I don’t).

Other features I found really attractive (and which are worth looking out for in other kits) are that it had a good solid lithium battery, purported to do 25km/hr on the flat with a range of 50-60km and the owner assured me that whilst the legal 200W version wouldn’t get me up Mt Nelson by itself, it would make the bends feel like I was just pedalling up a slight slope which is what I was after.

Figure 1 My converted bike.  Notice the front wheel.  Battery was originally in the bike bag on the rear rack where I also carry clothes and lunch.

You can buy 350W, 500W and I’ve even seen dual wheel 2000W versions, but 200W is the maximum legal allowed on Australian roads, so stick with this.

To put 200 watts into real terms, an average cyclist doing 20–25kms an hour is probably generating between 150 to 250 watts, which means that an electric bike is a bit like turning your bike into a tandem and putting someone on the back to put in the extra effort.  But don’t get too excited, professional cyclists are said to generate close to 500 watts when powering up the French alps, so you’ll only be faster, not superhuman.

Commute Time Comparisons

So down to the nuts and bolts of this comparison.  I decided the fairest way to compare different travel time options were 'door to door'. 

The car, which I’d assumed would be the quickest commuter option, actually takes around 20–25 minutes each way.  This surprised me at first, but then I realised that whilst it’s usually only 10 minutes drive down into town, it takes a further 10-15 minutes to actually find a (free) car park and then walk from the car into work.   So an average round trip is about 45 minutes.

The bus takes a bit longer, about 35 minutes door to door (25 minutes travel time, plus 5 minutes wait time for the bus and 5 minute walk to work), so an average round commute of 1hr 10 minutes.

Walking, not surprisingly, was the slowest option taking me about an hour and 10 minutes each way, so 2hrs 20 minutes return, but I must say it is a nice walk down through the bush.

My morning cycle to work is basically all downhill and I can literally cycle straight into my workplace, so it’s probably not surprising that the electric bike and normal bike are the fastest options for getting door to door in the morning at about 15 minutes.

However, on the ride home (up the Mt Nelson bends) it takes me about 40-50 minutes on my normal bike, so a total time of around an hour, putting it behind the car, but ahead of the bus in terms of total commute time.

And the electric bike?

Well I set off with some trepidation on the first trip home as I’m 6’1”, unfit, and weigh in at over 110kgs.  I was pretty concerned about how much difference that little electric wheel would really make. 

I was therefore blown away when I found that even allowing 5 minutes to get changed and pull the bike out of the bike shed at work, I can now consistently cycle home in under 30 minutes door to door.  This gives me a return commute of around 45mins which is actually the same as my car.  What’s more, I cycled home straight up the Southern Outlet on a whim one night and cut a further 5 minutes off my commute time, meaning that if I’m in a rush an electric bike is actually my quickest option. I didn’t expect that.

Cost

Well the cheapest commuter options, given I already own several bikes, is to either cycle or walk to work.  They both cost me virtually nothing, so they top the rankings on this criterion.

The return bus fare to and from my place works out at $7.20 per day, but you get a 25% additional recharge if you buy over $20 on a metro card, So I believe the real rate is closer to $6.60 per day.

The car is a bit tricker.  I normally park around Sandy Bay somewhere and walk into work.  Therefore my return trip is under 15kms a day, my car does about 11kms/litre and fuel prices are currently around $1.30 a litre (note this was written in 2010).  That means the return trip would cost me about $2 a day in fuel.

Now I know some smart person will be saying at this point, “but that doesn’t take into account the full cost of running your car”, and to be honest having just forked out $350 for two new tyres and just over $1,000 for my last major service I tend to agree.  So just for completeness, if we use the ATOrate for vehicles with a 1.6 to 2.6L engine of 74 cents per kilometre, then suddenly my vehicle commuting costs are over $11 per day.  On those odd occasions I have to pay for parking as well you can add another $8 - $10 to the cost, so depending on how you look at it a car ranks somewhere near the top, or right down the bottom.

Finally, the electric bike.  I purchased an Arlec energy meter, and measured how much it cost me to recharge my battery after a ride home assuming 20 cents per KWH which is about the average for my last power bill.  The charger draws 100 watts, and after averaging out a weeks recharging my little unit tells me it is costing me the princely sum of 5 cents per day to recharge the battery.

The battery is meant to take about 5 hours to fully recharge, and I’m finding it takes about 2-3 hours for my commute, so I’m only using about 50% of the power.  I’m told under lab conditions it should be good for about 1,000 charges at this rate, but a realistic maximum life would be about 5 years.

The unit cost $890 delivered to Hobart, so based on my usage to date, that’s a capital cost of about 90 cents per day compared to a cars $11 a day.   For those of you who run on caffeine like me, that less than a quarter of the daily cost of my latte addiction.

Exercise Factor

But isn’t riding an electric bike just being lazy?

To get some feel for this I dutifully strapped on my Polar Heart Rate monitor (yes, even when driving home in the car) and measured how many kilojoules I used up through the different options.

What I found out from this is that if you want to get fit, then power walk.  To get home in around 1hr 10mins isn’t a walk in the park, my heart rate was up over 140 bpm most of the way and I burned a very nice 2,400kj,  That’s just over 2 Mars Bars.  Riding my normal bike up the bends is also a good way of getting exercise, and according to my heart rate monitor I burn around 1,600kj on my commute home (cycling via the bends is a much longer distance than just walking home).
New Picture 1
Figure 2 Heart rate and climb for commute home on electric bike.

Now, there’s no way that a 200W unit can get you up Mt Nelson without at least some help, and I still find my heart rate is up between 100 and 140 bpm riding home via the bends, and going up the Southern Outlet it gets up to 160 bpm which is a good workout zone in anyone’s books.  However the numbers are in and according to my HRM I burnt on average 800kj cycling up the bends and slightly more, around 900kj on the more intense trip up the Southern Outlet.  So that’s roughly half the exercise of normal cycling, but it’s also half the normal commute time.

I also wore my heart rate monitor in the car and bus, but unfortunately when my heart rate goes below about 60bpm, it doesn’t seem to record energy usage, so I have no readings for the bus, and it was about 250kj for the walk back to my car.

However, there is one additional thing to take into account when comparing these numbers.  What I’ve found is that  instead of regularly riding to work 1-2 days a week, I’m now riding to work 4 days a week, so I’m now actually getting about the same amount of total exercise on the bike just over a longer period.

Carbon Emissions

I tried to understand carbon emissions sometime back, but decided that it is really way too difficult to comprehend beyond the principle that less is better than more.

This much I do think is true.  If I walk or ride my bike, then my carbon emissions should be practically nil.

I’m also going to argue that unless lots of other people also stop catching the bus and they discontinue the service, my being on a bus or not makes no difference to its carbon emissions as it will still be running regardless, so I can’t really claim any C02 savings from not catching the bus.

The electric bike is difficult, it does consume energy, but mainly Hydro, so I’m guessing it’s impact is pretty near zero.

A good rule of thumb for an Australian vehicle is that every litre of petrol equals about 2.3 kilograms of CO2 emissions, so if I use about a 1.5L each time I drive to work, then this equates to about 3.5 kgs of CO2 a day.  Looked at another way, if I now commute on my bike an extra 2 days a week over 50 weeks that equals about 0.35 tonnes less CO2 emitted each year. 

Unfortunately Tasmania’s CO2 emissions in 2010 were about 8.5 million tonnes per year so we’ve still got a way to go, but I’m doing my little bit.

The Other factors

There are quite a few other factors which you also have to think about for each alternative. 

Walking and cycling are both great exercise, but I do have to carry clothes to work, and the crinkled shirt look isn’t always the best.  I often end up having an extra shower when I get home as well, and of course there’s the rain and cold which takes a bit of a head space shift.

Buses may be sold as being more convenient door to door, but I work pretty flexible hours and actually found the bus timetable a little bit inconvenient.  I really noticed the cost of buses due to my having to pay every day, I found the seats a little cramped, I still got wet and cold waiting for the bus on rainy days, and unlike all the other options, I couldn’t stop off at the grocery store to pick up some milk or veggies on the way home.

A car was probably the most convenient, but only because I’m prepared to get to work before 7.00am. If I arrive much after that, the good parking spots have usually gone and the extra walk time means the electric bike starts moving ahead.  I also get nice and wet in the rain walking from my car, so no great advantage there.

How much weight people put on these is up to them, and like all things, you get used to them after awhile

Conclusions

Comparing the different options side by side (see Figure 3) has lead me to the conclusion that the best all round commuter option for me is the electric bike.  It’s the quickest, cheapest and most flexible option, and I get a good 25 to 30 minutes exercise at the end of each day. 

table
Figure 3 Summary comparison

Having said that, I was surprised how much I enjoyed the walk to work, and now walk to and from work on Monday’s for the exercise, I electric bike commute Tuesday to Thursday, and I drive to work on Friday, getting in early, but with my MTB in the back so I can head into the foothills of Mt Wellington for a Friday evening ride.

However, things haven't been all smooth sailing.  My conversion kit has had several problems over the years with wires coming loose and the unit overheating and melting cables.   The initial battery also failed after about 12-18 months, and although Solarbike were great in providing a new battery at below cost, it still cost me around $400 to replace it.  I also found (and I don't know why this would be) that the bike seemed less powerful with the new battery.

Just recently I had a chance to ride one of Ecobikes top of the range bikes and I was just blown away by how much more powerful and smooth it was, and also how much quieter it was than my bike.  My bike generates a slight whirring noise which doesn't annoy me, but it's not silent.  The bike I tried from Ahmet was just pure silence.

The final word of advice I will give to anyone considering purchasing an ebike/pedalac is to realise that you are now going to accelerate from lights and go up hills much faster than motorists expect and this is really important from a safety perspective.  

On several occasions I've accelerated from the lights and had a motorist try and get around me only to find that due to my speed they don't get past as quickly as they expected with the end result being that they have had to cut in dangerously close in front of me.  I've also had a few motorists who come up behind me going up hills and no doubt subconsciously just see a fat guy on a fully loaded mountain bike slowly turning over the pedals so make a mental calculation that I'm doing 10km/hr and without even thinking about it go to overtake only to find that they've misjudged the distance they need to get past me because I'm actually going at 20km/hr.

My experience in these situations is that cars will just pull in to the left right over the top of you and that can be dangeourous so I'm always doubly aware now of who is behind me.  If I hear a car coming to overtake and I judge it to be dangerous I have no qualms in dropping speed quickly or pulling way into the side.

But don't let that put you off, it's just not something that had occured to me and it did lead to one or two tight situations hence my advice here.

John Dawson

Note: This article was first written for the Bicycle Tasmanaia Newsletter Spoke in November 2010, and has also been published in DIER's Intranet.  It has been updated for this website in June 2013, and yes I'm still riding my electric bike to work.