Are ebikes dangerous?

[Ravi Kempaiah]

Cars have their place, not trying dis them but for short commutes (~5 miles), cars lose by a big margin and creates a lot of congestion/pollution etc.

We shouldn't move from one extreme to the other (cars to bikes, totally), but if we replace ebikes just for two days in a week, it could make a significant impact.

 

[Admin]

Good point Ravi, there's definitely a balance to achieve with different transporters. Though, I wouldn't mind if we replaced all internal combustion (ICE) driven vehicles with the likes of these:

 

[Ravi Kempaiah]

It would be really nice if we shifted from ICE to electric vehicles.
If we were to do that, we should be careful enough not to create another problem by depleting Lithium resources in the world. In terms of ebike systems, 36v 12Ah system is roughly equivalent to 432Wh, which translates to 43 grams of lithium. So, Neo Jumper has 43g of Lithium in it, Stromer ST1 elite has 40g-45g of lithium in it...so on.
Here is an analysis from a Stanford group:

How Much Lithium We Need
Lithium-ion electric vehicles can be designed with a large variation of battery capacities, so I will (somewhat arbitrarily) base my analysis on the Nissan Leaf electric car, which has a 24 kW·h battery. There are electric cars with smaller batteries than the Leaf (e.g., Chevrolet Volt) and larger batteries (e.g., Tesla Model S), so the Leaf's battery strikes a rough median. Every 10 kW·h requires 1 kg of lithium, so it takes at least 2.4 kg of lithium to make this battery.

If all other lithium industries suddenly evaporated, we could imagine using the entire world lithium production to make nothing but Nissan Leafs. At 2 × 10^7 kg of lithium per year, we can make 8.3 million of them. Using all 9.9 × 10^9 kg of the world's lithium reserves, we can make 4.1 billion Leafs; using all the identified lithium resources (2.55 × 10^10 kg), we can make 10.6 billion Leafs.

If we would like to have a North American standard of living for everyone in the world – say, 1 car for every 2 people – then we would need about 3.4 billion Nissan Leafs. This would use 32% of the identified resources (all known lithium in the world), or 82% of the reserves (all lithium that is currently economic to produce). Even with widespread recycling, that seems like an unsustainable prospect.

Remember that the limits on battery capacity are fundamental. The only ways this percentage can go down are:

1. Battery capacity exceeds 73% of the theoretical maximum (unlikely)
2. New deposits of lithium are discovered and made economic (unknowable)
3. Smaller lithium-ion batteries are used (shorter range)
4. Fewer cars are built with lithium-ion batteries.

This suggests to me that if all the world's cars are going to be made electric, it is likely that a mixture of battery technologies will be used. It is certainly possible to build millions of electric vehicles with lithium-ion batteries, but it may not be possible to make billions of them.

Source: http://large.stanford.edu/courses/2010/ph240/eason2/

 

[calvin]

Ravi, not only a mix of battery technologies but a mix of energy delivery systems. One I was thinking about was along the lines of supercapacitors: ( http://en.wikipedia.org/wiki/Supercapacitor ) that pick up energy quickly. A possible implementation would be akin to slot cars ( used to be popular many years ago), they used brushes that skimmed along a metal track to drive their miniature motors. Full size cars could use the same technique to keep the supercapacitor charged, this would eliminate the battery. This article does not address the problem of possible explosions, which as I remember, was the fly in the ointment.

 

[Ravi Kempaiah]

Calvin, good to see that you are thinking along those lines.
Last year, some of my friends and their team at UCLA published a groundbreaking report in Nature journal about graphene supercapacitor created using a normal DVD burner and graphene sheets.
People are working on it tirelessly and here is a video and what people on Tesla forum think of it. The technology is far away from being implemented in cars but we should get there in 4-5 years.

Video:

What people on Tesla forum think of it (read the comments):
http://www.teslamotors.com/forum/fo...-pencil-lead-and-dvd-burner-will-change-world

The link to original paper:
http://www.nature.com/ncomms/journal/v4/n2/full/ncomms2446.html

 

[calvin]

Thanks Ravi, another interesting reply. Perhaps someday they'll be able to scaleup/ pile those graphene sheets upon each other and connected them all utilizing something like a 3-D printer. Then we'll have a ebike with a 200+ mile range. Anything that can hold that kind of charge would be dangerous. Sparks, fires, explosions and electrocutions! Oh my! In fact I am mildly worried even about 48v or 72 volt batteries... under some conditions... rain... or just putting my finger where it ain't supposed to go... Ouchie!

 

[oilerlord]

Electric bikes make perfect sense but electric cars are ridiculous on so many levels.

- It takes 5 hours to "fill-up" for the range equivalent to about one gallon of gasoline
- Ford Focus electric: $37,000. Enough said.
- The 600 lb battery in the Leaf costs Nissan approximately $18,000 each.
- Turning on the heater or A/C could mean you won't have the range to make it home before the battery dies.
- Tesla makes more money selling carbon credits than they do selling cars.
- The government (all of us) pays out a $7500 rebate on every electric car sold.

The biggest reason these cars exist is because the government has mandated automakers to sell Zero Emission Vehicles. For example, Honda will sell approximately 225,000 cars in California this year. 2250 of these need to be ZEV's. Honda (and every other brand) loses money on every EV they sell, but it's the cost of doing business.

 

[Admin]

Great point Ravi and one that I've been familiar with both in terms of material constraints and the geo-political constraints surrounding them. Capacitors seem like a good next step, they are used for dynamo powered LED lights on a lot of European bikes. I think the challenge and limiting factor right now is weight.

oilerlord, one of the reasons I'm so passionate about ebikes is that they don't require government subsidies to make business sense. That's not to say I don't appreciate or agree with investing (even subsidizing) future sustainable technologies. People (my Grandpa) complain about technology that doesn't make sense... requires government support... but what about the gray costs like pollution? Who is paying for that? We all are, our children and their children are, the plants and animals we rely on also pay for it and it's a much higher cost than $7,500 just a tragedy of the commons and short sighted, selfish actions.

 

[oilerlord]

I absolutely agree everyone needs to do their part to make the planet a better place to live. We planted over 200 trees & shrubs on our property (where none existed before). On on my way to Seattle today, my VW TDI wagon achieved over 50 MPG on the highway. In spite of my car's excellent fuel economy, I still plan to ride my e-bike commutes and short errands instead of firing up the diesel. No doubt that every little bit helps.

I didn't want to come off sounding like a bitter grandpa. I'm sure we both agree that it makes much more sense moving one human 40 miles on a 6 pound battery (on an e-bike) than it does 40 miles with a 600 pound battery in an EV. Any positive environmental impact is completely neutralized by the massive carbon footprint created in the average EV's manufacturing process. That isn't to say we shouldn't keep trying to develop, improve, and hopefully reach a point where EV's make environmental and economic sense but the carbon credit shell game that's being played today only benefits likes of Tesla and Al Gore.

 

[Admin]

Hey oilerlord, I disagree that the positive environmental impact of electric powered vehicles is neutralized by the carbon footprint created in the manufacturing and disposal process. The production of a new EV or ICE vehicle is similarly harmful to the environment (paint, metal, shaping, foams) and indeed a battery is more harmful to produce and ultimately recycle but this is only part of the story.

Cradle to grave over an average lifespan of an automobile (100K to 200K), an EV is much more efficient because it uses locally produced electricity coming from regulated power plants and perhaps solar or wind through net metering (the electric grid is constantly getting cleaner while old automobiles are constantly getting less efficient and dirtier). I believe there is similar natural and geopolitical harm in sourcing Lithium as with Oil but once a battery is produced, it does not have to be re-mined and shipped across the world over and over to power the car. That can be left to a wide range of alternative, perhaps more stable and efficient, sources.

In Colorado a grid powered electric car is equivalent to about 30 MPG, whereas in California it’s up around 70 MPG (based on energy sources feeding in: wind and solar) . . . The vehicle manufacturing of a gasoline car is just 40g CO2e/km compared to 70g CO2e/km for an electric vehicle. This is because we have accounted for both a greater manufacturing footprint and lower lifetime mileage in an electric car (as the battery wears out).

The following image shows the miles per gallon equivalent that electric vehicles achieve based on their location of charging around the world. Note that in America this averages out to 40mpg based on how we produce electricity (with coal and natural gas) compared with Brazil and Paraguay where they produce electricity with hydro electric dams (which may still be destroying habitats... but at least the electricity is polluting less). Hydroelectric dams rely on the natural evaporation and rain systems that replenish rivers and lakes, they are essentially solar powered as heat from the sun causes liquid water to phase shift into vapor and eventually condense and rain back down. The second image shows the CO2 output of electric vehicle production. Data and image source here.



One final consideration... regardless of actual energy use and geopolitical context. Think about where CO2 is actually emitted. On ICE vehicles we put the tailpipe at the rear (because exhaust smells bad and is toxic... often used in garage suicides). If we are going to emit pollution, doing it through a regulated, highly filtered coal or natural gas plant outside of town seems like a preferable solution than in our communities.

I agree that electric drive and battery technology can still be improved. By purchasing one of the existing products you are helping to fund future investment in the space and signal to companies and governments that efficiency is in demand. Sometimes I hear people preaching about "voting with your dollars" and I think that's worth considering here as well.

 

[Electric Bike Specialists]

Hey oilerlord, I disagree that the positive environmental impact of electric powered vehicles is neutralized by the carbon footprint created in the manufacturing and disposal process. The production of a new EV or ICE vehicle is similarly harmful to the environment (paint, metal, shaping, foams) and indeed a battery is more harmful to produce and ultimately recycle but this is only part of the story.

Cradle to grave over an average lifespan of an automobile (100K to 200K), an EV is much more efficient because it uses locally produced electricity coming from regulated power plants and perhaps solar or wind through net metering (the electric grid is constantly getting cleaner while old automobiles are constantly getting less efficient and dirtier). I believe there is similar natural and geopolitical harm in sourcing Lithium as with Oil but once a battery is produced, it does not have to be re-mined and shipped across the world over and over to power the car. That can be left to a wide range of alternative, perhaps more stable and efficient, sources.

The following image shows the miles per gallon equivalent that electric vehicles achieve based on their location of charging around the world. Note that in America this averages out to 40mpg based on how we produce electricity (with coal and natural gas) compared with Brazil and Paraguay where they produce electricity with hydro electric dams (which may still be destroying habitats... but at least the electricity is polluting less). Hydroelectric dams rely on the natural evaporation and rain systems that replenish rivers and lakes, they are essentially solar powered as heat from the sun causes liquid water to phase shift into vapor and eventually condense and rain back down. The second image shows the CO2 output of electric vehicle production. Data and image source here.

View attachment 430 View attachment 428

One final consideration... regardless of actual energy use and geopolitical context. Think about where CO2 is actually emitted. On ICE vehicles we put the tailpipe at the rear (because exhaust smells bad and is toxic... often used in garage suicides). If we are going to emit pollution, doing it through a regulated, highly filtered coal or natural gas plant outside of town seems like a preferable solution than in our communities.

I agree that electric drive and battery technology can still be improved. By purchasing one of the existing products you are helping to fund future investment in the space and signal to companies and governments that efficiency is in demand. Sometimes I hear people preaching about "voting with your dollars" and I think that's worth considering here as well.

Found this the other day:

• http://www.ebikes.ca/documents/Ebike_Energy.pdf

EBIKE VS. MAN

Obviously, I'd wait for a more reputable study to start arguing that Ebikes are more efficient bicycles, but it's a fun read. You can follow up more with his sources.

 

[James]

Found this the other day:

http://www.ebikes.ca/documents/Ebike_Energy.pdf

EBIKE VS. MAN

Obviously, I'd wait for a more reputable study to start arguing that Ebikes are more efficient bicycles, but it's a fun read. You can follow up more with his sources.

That article is 10 years old! What insight the author (Justin Lemire-Elmore) had to predict the battery futures. Another Ebike user that is WAY smarter than me!

 

[Admin]

Excellent study Chandlee! I'm actually going to attach it to my post here in .pdf form in case that link goes away. In summary... given the energy cost of food, shipping, eating and pedaling output on regular human-powered bicycle compared with the cost of producing electricity and using it directly for pedal assist. Ebikes are more efficient and Lithium-ion is the most efficient battery chemistry (even with their low estimate of 500 charge cycles before degredation).

The results show that lithium-ion is clearly the most energy efficient chemistry, due to it’s light shipping weight, low manufacturing costs, and high charging efficiency . . . The above figures were all produced by assuming average or typical cases. To be fair, it is entirely possible for a bicycle rider to deliberately eat only locally grown and unprocessed foods. In that case, the ratio of primary energy to food calories is closer to 1:1 (Günther 3). Combined with a metabolic efficiency of 25%, this increases the human energy efficiency to 1:4, slightly better than the lithium-ion electric bike . . . Despite the intuitive sense that electric bikes would require more resources than regular bikes, life-cycle analysis shows that they actually consume 2-4 times less primary energy than human riders eating a conventional diet. This conclusion is largely due to the considerable amount of transportation and processing energy that is associated with our western food system.

The study in question was produced as a term paper by Justin Lemire-Elmore, published on April 13, 2004 using Canadian figures and sources.

 

[BostonSteve]

Not everyone likes ebikes.

In China, they're actually known as the "silent killer" because no one hears one before it hits you. They've started outlawing them in certain cities there. NYC has passed it's second law banning ebikes from city streets. Ebikes have found a "grey area" in the law allowing for 28 mph assist.

So:

1. Do you think ebikes are dangerous?
2. Have you heard complaints about ebikes on the streets?
3. Do you think ebikes will continue to have trouble with the law as they become popular?

Obviously we have our views here, but I was really interested in hearing what you guys think.

1. I have been bike commuting and road riding for 30 years. Originally I was pretty positive about ebikes. It did not interest me but could see for hauling kids or shopping could be a good idea. I do not feel that way any more. Ebikes really are not bikes. They are more like a mopeds. They are too fast for a bike lane and too slow for a car lane. But they ride in the bike lane. I am sure we are going to see a lot of accidents as adoption increases.

2. Not yet

3. I really hope ebikes adopt all the safety considerations as any motorized vehicle. They have no business in bike lanes or around cyclists.

 

[OrangeWagon]

I'm not sure if ebikes are any more dangerous than a regular bike. But I think an speed limit for assist (or throttle) makes a significant difference on that area.

I have a RadWagon with assist limited to 20mph.
And while I see significant help on climbs (12-15mph on the RadWagon vs 5-8mph on my road bike), on downhills I go way faster on my road bike. Then on flats I can sustain 22mph average on the Wagon (with help of my own power), but on my road bike I can also do 22mph too (granted... not for a very long time).

So the real advantage is on the climbs, and still within bicycle-speeds so I don't think is much more dangerous than a CAT5 roadie on their 15lbs bike

Of course if you don't have controller-enforced speed limits (per se 20mph), and you zoom by at 50mph on the bike lane while still expected to be considered a bicycle, then I think it's a different story.

 

[Dewey]

1. Do you think ebikes are dangerous?
2. Have you heard complaints about ebikes on the streets?
3. Do you think ebikes will continue to have trouble with the law as they become popular?

With regards to #2, in the District of Columbia, some of the complaints arise from municipal regulations that are being misinterpreted by the D.C. Dept of Transportation. Official guidance from the DC DoT non-traditional vehicle fact-sheet appears to mis-interpret 18 DCMR §§ 1201.18 by claiming motorized bicycles are not permitted in DC "bike lanes", but that rule applies to "off-street" sidewalk, bikepath, or bicycle routes. Rule 18 DCMR §§ 1201.19 states "a motorized bicycle may be operated on any part of a roadway designated for the use of bicycles". Class 1 pedal assist and Class 2 throttle e-bikes that are motor limited to <20mph are classed as motorized bicycles and are permitted in on-street DC bike lanes and protected bike lanes as they are in Virginia and Maryland.

The Park Service is not listening to the local bicycle advocacy group request for on-street bike lanes on Memorial Bridge when at present there is no safe way for cyclists to cross the Potomac bridges except off-street sidewalks/paths. This situation needs to change to protect Class 1 and Class 2 e-bike riders and pedestrians alike.

 

[Over50]

...3. I really hope ebikes adopt all the safety considerations as any motorized vehicle. They have no business in bike lanes or around cyclists.

The other day I headed out of my downtown for my commute home. Riding my ebike along the water front trail which had a fair amount of pedestrians inclusive of small children darting in/out of their parents legs, excited to be by the river. I was keeping my bike very slow and riding behind two regular bikes. From behind came two cyclists - young guys late teens early twenties on mountain bikes. Riding fast in and out of people. They startled a number of pedestrians who didn't hear them coming. They passed me and the other two bikes in a crowded area and headed on through more groups of pedestrians. They weren't on ebikes. Just regular cyclists being irresponsible. Seems a lot depends on the cyclist's behavior regardless of e-assist or not. On my commute out of my downtown, I ride a few miles on a dedicated paved bike path. Two lanes for bikes and one lane for joggers/walkers. I keep my speed slow because posted signs say "no motorized vehicles" and because it is the obvious thing to do on that type of multi-use path. On that path, at 15 mph or so I've been passed by road bikes. In the neighborhoods on city streets at about 20 mph I've been been passed by road bikes. On city streets with bike lanes I've been passed by regular bikes and I frequently pass regular bikes. If I'm in a bike lane and I don't have a safe area to pass I wait and ride behind the other cyclists until I can pass using the car lane. Seems to me just as with auto traffic much responsibility rests with the driver/rider to be considerate and to drive/ride safely. My ebike is a long way from being a moped. I'd say I blend in really well with the other cyclists I encounter in my commute and one would have to look pretty closely or have a trained eye to see that I was on an ebike. From the way I ride relative to other cyclists, you'd never know I was on an ebike. It isn't like I'm zooming by all the other cyclists. Definitely I think ebikers can ride and blend with other cyclists safely.