
What are the different kinds of electric bikes and their price ranges?
In YouTube comments I regularly see people upset by the perceived high price of electric bikes, claiming that a used car would be cheaper… I think they often fail to recognize the high price of car repairs, preventative maintenance like oil changes, insurance, licensing and parking. Cars and ebikes are not investments, they are tools or toys that depreciate with use, their true value is highly dependent on the environment and task at hand or entertainment preferences of the owner.
So for example, if you live on a highway and commute 20 miles to work each day an ebike might not be a great tool. To that I say, consider renting an apartment near your job and buying an ebike!
Life changes aside, let’s do a quick hypothetical costing example, if you took all of the car maintenance stuff away for a moment and just looked at a $3k brand new car vs. a $3k brand new ebike and left gas at $2 per gallon… an average electric bike gets ~20 miles per charge and cost less than $0.15 to fill (even using Hawaii’s scale-tipping $0.37 per kilowatt-hour rates). So let’s say that your car gets 30 miles per gallon and a gallon is $2 and your bike gets 20 miles per charge and a charge is $0.15, the bike is way cheaper right? But that’s not the whole story. A premium electric bike battery costs anywhere from $500 to $800 to replace and lasts 1,000+ charges so let’s treat this like a fuel cost and divide $500/1,000 charges… we get $0.50. So we add the $0.15 charge cost to the $0.50 battery use cost and get $0.65.
Basically, electric bikes are about three times less expensive to operate than cars from a current fuel cost perspective. Beyond user operating expense they also cost less in terms of negative externalities because they don’t create localized pollution which contributes to health issues and spoiled views of the mountains. Ebikes are awesome but so are cars and even when self driving electric cars replace the costs of ownership and reduce pollution, there will still be enormous health and social value to cycling… and why not have an assisted cycle?
It’s like comparing a mechanical typewriter where you forcefully push the keys down to modern laptop that can be operated much easier, faster, in more environments and it will save your work digitally! Maybe some people would claim that the sheer muscular joy of old fashioned typewriting and the ever present danger of a misspelling will always hold a place in their hearts… and good for them, it’s not really an issue and with ebikes or traditional bikes we can still ride together and have fun!
How far can you typically go on a charge?
A good rule of thumb here is to divide watt hours by 20. So electric bike batteries have voltage and amp hours and a typical pack right now in the US is 36 volts of power with 10 amp hours of capacity for 360 watt hours total. If we divide 360 by 20 we get 18 miles. Given variation between throttle only electric bikes and pedal assist that 18 is really a floor that can go up as riders contribute pedal-power to the system or different drive systems are leveraged.
For example, mid-drive electric bikes can benefit from driving the rear cassette and gears to empower the motor for improved efficiency. In the same way that you would want to shift down when climbing (instead of standing up and working extra hard), so too does the motor and these mid-drive systems offer that flexibility because they pull the bicycle chain along with you. I’ve seen some electric bikes with that same “360 watt hour” battery capacity reach 50+ miles per charge on a low level of assistance (equivalent to half of the rider’s pedal power output). That’s pretty amazing to me.
The current best DYU model mileage is 60km, which is up to satisfaction for most city commuting needs.
Are e-bikes much faster than regular bikes?
Not really, most low-speed electric bikes won’t go over 20 miles per hour under motor power alone. You can always pedal faster than that or drop a steep hill but federal regulation limits this top speed in exchange for classification as a “bicycle”. Some recent compromises have been made whereby pedal-assist electric bikes may reach ~28 miles per hour assisted but only if the rider is pedaling rigorously. A similar class of electric bikes called “speed pedelecs” exists in Europe and have become popular for commuters.
Take note however that efficiency drops off significantly as riders gain speed as a result of drag. That is “forces acting opposite to the relative motion of any object moving with respect to a surrounding fluid” or in this case air. The power needed to push an object through a fluid increases as the cube of its velocity while “air drag” is approximately proportional to the square of velocity.
In short, as you go beyond 15 mph on an ebike, drag really starts to cut into the range you can achieve so speed comes at a high price.
So an e-bike with a speed of 25km/h like DYU is safe and good enough for daily travel.