Cycle9.com » Energy

What’s Peak Oil Got to Do With It? Go By Bike Episode 44

elise — Fri, 30 Jul 2010 12:17:48 +0000

What is Peak Oil and what can we do about it?

I had the opportunity recently to listen to a talk and discussion about peak oil and climate change here in our local town . The talk was interesting and a good presentation of the topic, but also interesting was the reactions of people in the crowd. Here’s what happened:

It’s a serious issue that we shouldn’t take lightly, but it’s also easy to feel overwhelmed and get into gloom and doom mode. I found my way to take action on this issue, both personally and through starting Cycle 9. What about you? Is Peak Oil something that motivated you to ride more?

What are people in your areas doing about sustainability, climate change and energy use?

Here are some links to :

General information about Peak Oil

http://en.wikipedia.org/wiki/Peak_oil

http://www.energybulletin.net/primer.php

and the Transition Town Movement

http://www.transitionnetwork.org/

-Elise

o By Bike is a daily video series that talks about how to be green by riding more and using your car less, including electric bikes, electric kits, cargo bikes, bike safety, and getting motivated to bike

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Stop Drilling? or Stop Driving! – Go By Bike Episode 22

elise — Tue, 18 May 2010 17:36:27 +0000

Environmentalists need to examine if their words and actions go together

As the Deepwater Horizon oil disaster in the gulf continues to wreak environmental havoc, I’m sure the reaction from many environmentalists will be loud calls to stop drilling and curtail offshore oil drilling. This may be something we should do, but I wonder how many of these same environmentalists will continue to drive their cars every day, mindlessly burning up oil while they wait for electric or alternative vehicles to solve their transportation guilt. In today’s episode of Go By Bike, I talk about his connection.

For a more detailed discussion of this viewpoint, see this excellent article from Jason Henderson, Geography Professor at San Francisco State University .

Send your comments below!

-Elise

Go By Bike is a daily video series that talks about how to be green by riding more and using your car less, including electric bikes, electric kits, cargo bikes, bike safety, and getting motivated to bike

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Why Electric Cars are NOT the Answer – Go By Bike Episode 14

elise — Mon, 03 May 2010 21:07:29 +0000

Will electric cars solve our oil dependency problems?

There’s a lot of hope and hype about electric cars, with just about every car company jumping on the promised future of these vehicles with a design of their own. But electric cars just don’t solve one fundamental problem of transportation by car. What problem is this? Watch to find out.

What do you think about electric cars? Give me your comments below.

-Elise

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Volcanos, Flowers, and Globalization – Go By Bike Episode 7

elise — Thu, 22 Apr 2010 16:46:33 +0000

How does the volcano in Iceland affect Fresh Flowers in South Africa?

Welcome to Go By Bike! In today’s episode of Go By Bike, I talk about our global connections, including how a volcanic eruption has worldwide ramifications.

I started this series to talk about how to ride more and use your car less, including electric bikes, electric kits, cargo bikes, bike safety, and getting motivated to bike. Using your car less reduces your carbon footprint, saves energy, helps the environment, keeps you healthy, and makes your community a nicer place to live, so overall most people would agree it’s a good thing.

What are your thoughts on globalization?
-Elise

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Using our cars is bad for us! – Go By Bike Episode 3

elise — Fri, 16 Apr 2010 17:06:24 +0000

Give your kids a cleaner, brighter future

Welcome to Go By Bike! I started this series to talk about how to ride more and use your car less, including electric bikes, electric kits, cargo bikes, bike safety, and getting motivated to bike. Using your car less reduces your carbon footprint, saves energy, helps the environment, keeps you healthy, and makes your community a nicer place to live, so overall most people would agree it’s a good thing.

In today’s episode of Go By Bike, I discuss energy use, the environment, and one key thing we can do right now to be green and give our kids a better future…

What do you think? Can you replace some short car trips by bike? Send me your comments.

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To Maine on the train

Morgan Giddings — Sun, 23 Aug 2009 12:23:00 +0000

Jim Kunstler is famous, or perhaps infamous is a better word, in the “peak oil” community for his prophecies of gloom and doom to be set upon the USA due to our profligacy and oil dependency.

Kuntstler is a controversial figure, in part because he constantly predicts doom to beset us, and in part because of his rather loudmouth style that includes lots of swear words to make his point. While some of what Kunstler says may hit some underlying truths about whether our lifestyles are sustainable (or not), his message is weakened by a few problems. First, the constant prophecies of doom don’t come true. And second, he is a hypocrite.

In his most recent blog post, titled “The First Die-Off” he talks about driving his car back from a vacation on Cape Cod, and being stuck in traffic. He claims there is “no train service” and uses that as his excuse for having driven the car.

Please.

I just came back from a trip to Maine on the train, with 3 small kids in tow. We stayed on the beach in a town not all that far north of Cape Cod (south of Portland, Maine). The train was comfortable, relatively convenient, and relatively cost effective. We rented a bike once we were there, and used it for most of our errands.

Nina on the beach by Biddington Pool

Kid on the beach in Maine

It annoys me to no end to have someone like Kunstler constantly harping on “the end of the world as we know it,” and then in the very same essay, to be so blatantly participating in the very activities he laments as leading us to The End.

In fact, from the comments section by user “signalfire” after his blog post:

Isn’t the problem that EVERYone thinks THEY are the ones who are ‘special’?? THEY deserve a holiday at the beach. THEY deserve cheap energy. THEY deserve big houses. THEY deserve their Escalades, Hummers and Jet Skiis..

This hits the nail on the head. Why does Kunstler preach that we’re going to have a massive die-off on the one hand, and yet so blithely participate in the very same activities, such as driving to and from the beach? People pay attention to him. If he had taken the bus, or ridden his bike, or taken the train, then his diatribes might not have seemed quite so silly.

I noticed something in the small town of Biddeford Pool that we stayed in. It was an excellent place for getting around by bike or foot – except that there was so much tourist-related automobile traffic, that it wasn’t that great. One of my friends there, who likes to bike, remarked that it would be great if there were less traffic. The very same person was the one out driving the car nearly every day to run this errand or that, such as to pick up morning newspapers.

Biddington Pool in Maine, Sunset

Biddeford Pool, ME

The main difference between my friend and Kunstler is that one might expect Kunstler to know better, given that talking about Peak Oil is the main focus of his life. His efforts to educate people on the topic are greatly diluted by such obvious hypocrisy.

I don’t claim to be perfect – I consume some oil, too. But I make efforts to minimize it, and set an example as to how life can be enjoyed with a minimum of oil. Aside from taking the train as frequently as possible for trips – which I’ve come to really enjoy – I like to show that bikes can be used for tasks that people often think of as requiring a car. The most recent example is the move of several heavy server systems from my Lab from an old location in an out of date server room to a much more modern facility. The computers are 8-core Apple Xserves, each weighing about 40 lbs. I readily carried two of them together, totaling about 80 lbs, on my bike, and the errand was far quicker than it would have been by car, because parking on campus is a nightmare. With the bike, I rode right up to the door at both the starting point and the destination. Later, when we have to move 40 of them, I’ll enlist the Yuba Mundo, a bike that can carry up to 400lbs or so of cargo. By moving 8 of them at a time, with each trip taking only 5 minutes, we can have the moving part done in under an hour.

Morgan Transporting Cluster Node

Moving 2 Apple Xserve servers on the electrified Surly Big Dummy bicycle

So I challenge James Kunstler: if you’re serious about all this gloom and doom, then go out and set an example of how to avoid it. Show us the alternative. Don’t just whine about how bad it is going to get. Help provide an alternative.

That’s what I’m doing in my “spare time” – helping customers of Cycle 9 find oil-free alternatives for every day errands and tasks. Really, I don’t have any spare time – with small kids at home and a more than full time faculty job, my life is often seen by others as “insane”. People ask me how I do it. How I do it is by being inspired to help people. The thing that keeps me going is seeing the joy of people whom we help discover there is a better way than dependency on the oil companies. A way that is healthy and brings regular joy in the way that being stuck in a car in traffic does not. The latest example is Cory, who is profiled in the next blog post.

Kunstler, it is your turn to help people find a better way, rather than just being seen as a whiner.

Solar at Shakori Hills: does it make sense?

Morgan Giddings — Sun, 19 Apr 2009 21:20:00 +0000

We had the pleasure of making it out to the Shakori Hill Festival today to let the kids participate in various events such as the Paperhand Puppet Intervention, and to listen to a bit of good music.

The organizers had a booth there, asking for contributions towards a solar electic system that would power the event in the future. The card indicates that 10,000 kilowatt hours (kWh) of electricity are used to put on the event. I applaud their goal to get off the grid. But the sea of cars I saw in the parking lot left me wondering: how much energy was used in just getting people to/from the event, in comparison to the 10,000 kWh goal?

Here’s my attempt to figure it out. When we were there on Sunday, there were perhaps 700-900 cars around. We can estimate from that a total of about 5,000 cars were driven to/from the event during the course of the four days (that’s an average of 1,125 cars/day, or 2,250 people per day if it averaged 2 people per car, probably a low estimate). The location is 17 miles from Carrboro, 40 mi from Raleigh, 35 mi from Durham, and 10 mi from Pittsboro. So we’ll average all of those at 25 mi (each way), for an average round trip of 50 miles. The fleet average for the US automobiles as of 2003 was 25 miles per gallon, so on average, 2 gallons of gasoline were burned per car trip to/from the festival. If our estimate of 5,000 car trips is accurate (maybe an underestimate?), that’s 10,000 gallons of gasoline burned up (526 barrels of oil).

Now, hold onto your seats. Each gallon of gasoline contains about 37 kilowatt hours (kWh) of energy. So, we have 10,000 * 37 = 370,000 kWh of energy burnt up to get people to/from the festival in their cars/SUV’s/trucks/motor homes.

That is, 37 times more energy were used to transport people to/from Shakori Hills, than would be saved if the festival organizers reach their goal of going all solar.

Here’s another way to look at it. An efficient generator will extract about 7 kWh of energy out of a gallon of gas (no, they are not very efficient, they only recover a small part of the 37 kWh contained in a gallon). So, to generate the 10,000 kWh of energy that the festival needs to run, that is about 1,429 gallons of gas, if they were to use local generators. Compare that 1,429 to our estimate of 10,000 gallons burned up getting people to and from. I.e., even using inefficient gas generators, generating all that power to run the festival would only take 1/7th the power that is consumed to get all those people to/from the event. 1/7th. That is sobering. (and note: even if everyone drove a super efficient hybrid like the Prius out there, and averaged 50mpg, it would still consume more than 3x more energy to transport people there).

And this is why all the peak oil people are so concerned about our future. They realize how much energy we are just burning up driving around in our gasoline burning cars. But most people don’t think about that. Even very “green” people just don’t realize how much energy is contained in each and every gallon of gas put into their cars. And, while I applaud the goal of Biodiesel, I had a look at the Piedmont biofuels website to see how much they produce. They produce “thousands of gallons per day” – so, basically, if every person going to the festival used biodiesel instead of fossil fuel, there would be none left in this area for any other purpose (such as powering tractors that help grow our food).

I don’t want to come off as overly critical of these efforts. Every small bit helps. But if people think these are solutions to fossil fuel dependency, they are clearly not. They are drops-in-the-bucket.

Anyway, I think if the Shakori Hills organizers can get the solar panels, it will save energy and have a positive effect – not only by the direct power saved, but by the example set. At the same time, they could have a vastly greater effect on energy usage for the festival (and also local pollution/noise/danger created by the cars) by implementing a bus system to/from the event. Or getting people to go out there on their electric bikes

Bike ride to Triad Electric Vehicles Association meeting

Morgan Giddings — Sun, 05 Apr 2009 00:06:00 +0000

Today I just got back from a nice bike trip with my daughter, to the Triad Electric Vehicles Association meeting, in Burlington, NC. I was invited to their monthly meeting to give a presentation about Lithium batteries and battery management systems, since some of the members are starting to contemplate moving away from lead acid batteries. In fact, two of the members have recently commissioned us to build custom packs for their EV’s.

We rode over there on my electrified Surly Big Dummy, with an eZee electric kit on front. We had 3 different LiFePo4 battery packs (48V x 10 amp hour (Ah), 2 x 36V x 10 amp hour, totaling about 1200 watt hours, which equals a 100 watt lightb

ulb running for 12 hours). I didn’t really expect to use that much battery power on the 33-mile each way ride, but I brought them for show and tell (and glad I did). I also brought some BMS boards (designed by the folks on Endless Sphere), PSI cells, and more. We also had all our overnight gear. So the bike was well loaded with us and all our stuff. I estimate that the gross vehicle weight was close to 400 lbs with us included.

While a round-trip 65 mile bike ride may not sound like a big deal to some folks who ride their road bikes 60+ miles in a day, this was a ride with precious cargo on the back, and a fully loaded bike, on some sections of busy road. I planned the route using Bikely.com, which allows mapping out a route using Google maps. I tried to choose a lower-traffic route most of the way, but some high-traffic stretches were unavoidable (why don’t they put shoulders on the roads in this part of the USA????)

We started out mid Friday afternoon, hoping to make it there before the main rush hour traffic hit. As soon as we got on the road, there were some serious headwinds. The national weather service reports winds averaging 15mph, with gusts up to 43 mph – coming straight from the direction we were going. I was sooooo glad to have electric assist. That would have been a miserable ride without. At one point, I was going full throttle (using about 1,200 watts) and pedaling full tilt, on flat ground into the wind, and only going about 15 miles per hour. Without electric, that would have been about 6 miles per hour. There were also some nice hills, too (totaling about 1,200 feet of up and down). Without electric, and with that headwind, the trip would have easily taken at least 4 hours. Despite the winds, we made it there in 1hr 45 min, at an average speed of just under 18 mph. But we burned up way more energy than I planned – about 24 watt hours per mil

e. (i.e., four miles riding would equal a 100 watt light bulb running for an hour). I had planned on 20 watt hours per mile. Glad I had those extra batteries!

Jack, one of TEVA’s leaders, graciously hosted us for the evening and let us crash at his place. We had a nice dinner and after-dinner discussion about quantum mechanics, consciousness, God, and evolution (I am making slow progress on a book about these subjects). We also had the obligatory discussion of the current financial “crisis”. Anyway, to bed very late, and up somewhat early next morning to head out for the meeting.

So I’m not someone to get shy in front of groups of people, since I give scientific lectures fairly regularly (just gave one last Thursday to an audience of 40-50 people). But this group was a bit intimidating, because there was only one other woman present, and it was about 20 guys, who were obviously quite tech savvy. Well, after some introductions and whatnot, we got down to business and I started describing the ins and outs of Lithium Iron Phosphate (LiFePO4) batteries for electric vehicles. I talked about keeping cells healthy, the benefits and drawbacks of these batteries, and discussed some basic design elements for battery management systems (BMSs), the electronic systems that keep cells healthy. There was some good discussion and questions. Afterwards, we went out to the parking lot to check out the various EV’s there.

Here’s an interesting observation that one of my hosts made: I was one of only 2-3 people who actually used an electric vehicle to get there, and mine was a bicycle.

This was a very interesting observation, so I’m going to sidetrack for a second on that. Why didn’t more people drive their EV’s over there? I can only guess: I think the biggest reason is that of the various people I talked to, many people had lead-acid battery packs that weren’t performing too well anymore, or didn’t have sufficient range, or… etc. One guy mentioned a story about being out in his EV one day and getting stranded when the batteries ran out, and having to walk 3 miles. So here’s the interesting thing. If a bike battery runs out, you can still pedal the bike. Even my nearly 400 pound cargo bike, if I had to, I could pedal it that whole distance. But I think the bigger take-home message is this – the main impediment to people using their EV’s more often is the batteries. For a bike, the battery is relatively small, and hence (though not cheap), not nearly as expensive as for a car or truck-sized vehicle. So nowadays, many people use lithium or at least nickel batteries on bikes, whereas most electric cars of the hobbyist variety are still lead acid. One older gentleman even prodded me a bit because he said he had access to very cheap lead acids, so he didn’t see why it was worth buying lithium batteries. I understand that point of view, that in an ideal world lead acids can run for a very long time, so why pay (lots) extra for LiFePo4? But, being in the e-bike repair business, I have seen so many “dead” e-bikes simply because the batteries died, and people hate having to replace them every few years. And it gets worse when you put them in a series string to produce higher voltage. Aside from the longer life and lighter weight of lithium, there is the lower hassle factor. If you get a working system with a good BMS (very important), it should give many years of service without issues. I used lead acids for many years before I switched. But now that I’ve “seen the light,” it is hard to fathom ever switching back to the heavy, bulky (though cheap up front) lead acids.

But anyway, some people tried out my Big Dummy and had lots of fun. Then a bunch of the members headed off to the Earth Day fair in Greensboro, and we got headed back to Chapel Hill/Carrboro.

This time, the wind was at our backs, and still pretty strong. Sweeeeet! There were a bunch of times we were cruising along with just pedaling, no electric power at > 20 miles per hour, a good clip for a 400 lb cargo bike. We made the return trip in just under 1:30 hrs, averaging almost 19 miles per hour, and using about 16 watt hours per mile. After a nice stop at a friends’ house along the way, we got back home. And after just having biked 68 miles on a fully loaded cargo bike in 1.5 days, I wasn’t totally wiped out (I definitely got some exercise, but not to the point of being wiped).

Total stats for the trip:

-Average 18.4 miles per hour

- 67.85 miles

- 3:40 minutes riding time

- 19.9 watt hours per mile

- total energy used by bike, 1,350 watt hours (for perspective, a typical gasoline powered car would use this much energy to go about 4-7 miles). I probably burnt another 400-600 watt hours from leg power.

I was nicely surprised by how well most drivers treated us. There was only one situation that made me nervous, a stupid dude in an ancient camper truck passed us at the same time there was oncoming traffic, and only gave 6″ to spare. I don’t know what his deal was, but maybe his engine couldn’t handle slowing down on the somewhat steep uphill we were on, without stalling. Anyway, here’s a plug for rear-view mirrors: I knew the guy was cutting it close, and I was prepared to bail out onto the grass if he got any closer, long before he was upon us. I don’t know how any cyclist can stand riding without a rear-view mirror. I use mine constantly.

But anyway, most drivers gave us wide berth, and we had a really nice ride through the countryside of the piedmont.

3 cheers for human-electric hybrid vehicles!

The slow ride: geeking out on energy

Morgan Giddings — Thu, 19 Feb 2009 00:55:00 +0000

When I’m biking, I often have a chance to ponder things. One thing I like to ponder is the amount of energy used to transport humans and things around. My electric bike is a great way to explore that geeky subject.

Today I did an experiment. I was riding my Big Dummy with a typical load, for a gross vehicle weight of around 300 lbs. I only used the electric assist to “take the edge off” the hills. I didn’t use it to increase my speed (except on hills), or to accelerate from stops. I was able to get my energy consumption for the round trip down to 6.3 watt hours per mile. In other words, my round trip consumed 90 watt-hours. Of course, I invested more of my own energy in the ride, because the ride was longer than usual, about 13 minutes extra. But I didn’t feel substantially more worn out or tired, because of using the electric on the hills.

For perspective, if I kept energy use at this level, with my single 10-lb LiFePO4 battery (48V/10Ah = 480 watt hours), I could ride 76 miles! I typically use more like 16 watt hours/mile, which would reduce the range to 30 miles.

The only real difference in the ride is the speed. Normally I average around 18 mph for the ~15-18 mile ride (depending on route). Today I averaged 13 mph. Wow, that seems slow! On my road bike, I would have averaged more like 17 mph on this route. Why such a difference?

I did a little mapping of my route using bikely, an online bike route mapping tool. It can show an elevation profile of the ride. I was amazed to find out that during my round trip of 17 miles, I do a total of 1000 feet of climbing (gross, not net)! That’s more than when I lived in a Canyon in the mountains of Utah. The difference is that here, it is not nearly as obvious, because that 1,000 feet comes as a series of small ups and downs (some of them quite steep). So by the end of the ride into the office, I’ve only gained a net of 50 feet, even though I pedaled up 550 feet of hills (and 450 more feet of climb for the ride home, with a net loss of 50 feet).

No wonder I was so slow on the cargo bike. I’m hauling at least 60-70 pounds extra compared to the road bike, with the Xtracycle, all my gear, the heavy gearhub, the battery, etc. Carrying 60-70 pounds up 1,000 feet is not a trivial energy investment. This was very instructive – I suggest that readers try it for their own routes, they might be surprised.

Now when people ask me whether I will “wean myself” from my electric assist, I will answer them: “let’s see you pedal a loaded cargo bike up a 17-mile, 1,000 foot climb every day without electric assist.” In reality, I would simply not do this ride every day (or more than 1-2 times per week) without electric. I would just be too wiped out to have the energy for everything else that needs energy in my life (like Cycle 9, and my full-time day job as a professor, or kids).

All of this generated some additional thoughts. When I show people the batteries for electric kits, they often ask me, “does it really make up for its own weight?” The answer is emphatically yes for shorter rides like this. On a normal day, I will do my 17 mile 1,000 foot climb with a 300+ pound bike at an average of 17 mph (riding faster than most folks could do on a road bike for this route). This definitely pays its own way. But, I wonder, how much climbing could I do, before I would I reach the “break even” point, where further climbing would just be me dragging the battery + motor up the hill. Here’s a rough estimate:

The 48V/10Ah battery weighs 10 lbs, or 4.5 kg. It holds 480 watt hours, which is about 1.72 million Joules. We’ll use Joules to figure out how much energy it takes to lift a 300 pound bike up a hill. Neglecting friction for the moment, the energy used in climbing is given by m g h, where m=mass of bike, g=gravitational acceleration, and h is height. So for my bike on this climb we have U (potential energy in metric units) = 136 kg * 9.8 m/s^2 * 304 m = 405 kJ of energy needed to lift the bike up those hills. If we figure the hub motor is only 80% efficient, then we used 506 kJ of energy, about 1/3 of the battery capacity. I’ll address friction losses later.

Now we can estimate for just hauling the battery and motor up the hills: the motor is another 8 lbs, or 3.6 kg. With controller and wiring added in, we’ll call it an even 20 lbs, or 9 kg. So, U = 9 kg * 9.9 m/s^2 * 304 m = 26,812 Joules, or accounting for 80% efficiency, 33.5 kJ. In other words, the energy used by the motor system to lift itself up the hills consumes only 2% of the energy it holds in the battery. We can approximate how far the system could lift itself before I would start having to lift it. Here, U = 1.72MJ * 0.8 (80% efficiency) = 1.37MJ = 9 kg * 9.8 m/s^2 * h. We want to solve for h, so: h = 1.37 MJ/(88.2 kg m/s^2) = 15 kM – yes, 15,568 meters. This system most definitely pays for itself – even if I’m climbing mount Everest. How high can it carry the whole bike and I, if I were too lazy to pedal? h = 1.37 MJ/(1332 kg m/s^2) = 1,208 M, or about 3,374 feet. Not bad – that’s a pretty big mountain.

So there we have it – the electric system pays for itself in spades where climbing is involved.

But what about friction?

So far, I’m having trouble finding good numbers for friction on a bike. I know this: The frictional losses due to wind resistance go up with the square of the velocity (v^2). That’s why when I increase my average speed from today’s 13 mph to my regular 17 mph – only a 4 mph difference, or about 25% – my energy usage goes up so much. I am burning up much more energy on friction – but I am also contributing less total leg power, because I have less total time spent pedaling.

Here’s a rough estimate: we know that all the potential energy gained in the 1,000 ft of climbing is burned up as friction on the way down the hills (I don’t use the brakes much since the hills are short). Typically on the downhills I am traveling closer to 20mph average. So, we can get a very rough estimate of total friction, by starting with U = 405 MJ = downhill frictional losses for the downhill parts, and figuring out how much I loose on the uphills. If my speed on the uphills is 1/2 that on the downhills (average of 10 mph), then the total wind resistance losses are 1/4 of that on the downhills. Plus, I’m sure there are some additional losses for bearings in the bike and static interaction of tire to road, which we’ll add in as a fudge factor of 100 kJ. So we have U = (405 kJ (downhill total) + 405 kJ * 0.25 (uphill wind) + 100 kJ (fudge)) / 0.8 (80% efficient) = 757 kJ = 210 watt hours. Yay – that is about what I actually end up using, except on days that I travel really fast, or have particularly heavy loads. So that means my estimate of frictional losses on the uphill parts, of about 205 kJ total, is in the ballpark. That’s about 57 watt hours, or 8 wh/mile burnt on friction when at low speeds (total input combining motor + legs - efficiency losses of both).

That’s way geeky. But, hey, it is nice to know where the energy goes, and more importantly, that my electric bike system really does carry its own weight (and then some). It all boils down to this:

1. If I want to save energy, I go slowly. It makes a very big difference.

2. At 10 mph, I’m burning around 6-8 wh/mile on friction (electric + pedaling), and at 20 mph it is around 25-30 wh/mile (electric + pedaling). At 30 mph, this rises to 60-70 wh/mile.

3. The electric system will carry itself, and me along with it, up some very big hills, as long as I don’t burn up its energy on friction by going fast

4. It is fun to ride a loaded cargo bike on a 17-mile, 1,000 ft hilly commute, often passing roadies and watching in my rear view mirror as they pedal really hard to try to keep up (and knowing that I’m being super energy efficient in the process)!

Work and pleasure

Morgan Giddings — Thu, 05 Feb 2009 01:57:00 +0000

Today I got to combine work and pleasure: I rode 38 miles round trip on my electrified Big Dummy (the Firefly) to Duke University. I gave a seminar on Bioinformatics, and then rode home. It was a cold day out (at least for these parts), with my ride home dipping well below freezing. I brought along a thermos with hot tea, and stopped several times to top off my tea cup (mounted in my handlebar beverage holder). On the way home, I even stopped at my favorite place to ~~waste~~ spend money, A Southern Season, to buy some more tea and sundries.

Why is such a trip even of note? For a couple reasons. First, today we spoke to one of our bicycle suppliers on the phone. He was asking us about electric assist, and saying that he didn’t really “grok” (understand) the whole electric bike thing.

Today’s trip is a perfect example of why an e-bike works. I have ridden many miles on road bikes; I could have ridden the ~40 miles on my (non-electric) road bike on a recreational ride in better weather – easily. HOWEVER, I wouldn’t have done that in a down coat, with insulated boots, with a thermos of tea, with a handlebar stereo, with a large U-lock, with a full change of dress clothes (to give the talk), with my computer, with a full array of bike lights for after dark, and other miscellany. If I had ridden my road bike with that assortment of gear, I would have arrived very tired out (and also about 1 hour later).

With the e-bike, I got two hours of exercise (I was pedaling moderately the whole time), but I did the trip in luxury (especially since the Big Dummy allows me to carry so much stuff). I never got cold, since I had plenty of spare warm gear, and big heavy duty boots, down parka, etc. I was drinking hot tea for the whole ride there and back. I had good tunes. In the narrow, fast moving parts of the road, I used the electric assist to keep my speed faster to not impede traffic. I hauled my load of stuff up some steep hills without problem. I arrived for the seminar feeling good from the ride, but not worn out. I left after the talk with plenty of energy, and had a (mostly) pleasant ride home, through some back neighborhoods up some very steep hills (to avoid the more traffic filled routes).

Simply put, I wouldn’t have done this trip without the electrified longtail bike. I would have ended up driving a car. Comparing the energy usage of that:

Car: 25 miles per gallon. That’s about 1,320 watt-hours (KwH) per mile. If I still had a Prius, that might have been as good as 45 mpg (doesn’t do as well in cold weather), or 733 watt hours per mile. In other words, each mile traveled in a Prius would have consumed the equivalent of 7-hours running a 100 watt lightbulb. For the whole trip, that would would amount to 27 kWh – the equivalent of leaving a 100 watt lightbulb on in my house for 278 hours or 11 days straight (that’s with the more efficient Prius!)

Bike: 18 watt hours per mile (about 1,833 miles per gallon). The whole ride consumed 684 watt hours of electricity. That’s equal to less than one mile in the Prius, and about 1/2 mile in the big car! I could charge my battery with the equivalent of 7 hours of 100-watt lightbulb usage, easily doable with the solar panel on my roof.

Why highlight the stark difference? Simple: I never used to think about how much energy I was using when I got into the car to drive. And I suspect most people don’t. Gas has been so cheap for so long, there is no motivation to think about it. But, when put in the above context, it is all the more clear how much energy it takes to move that hulk of steel around. It doesn’t matter whether the car is electric or hybrid or whatever. It is heavy, and it travels fast. Both of those factors mean that it is intrinsically inefficient, and consumes a lot of energy. For those folks concerned about CO2 emissions, the above numbers say a lot.

But here’s the sad part. I studied the maps carefully before going, to find a route where I wasn’t going to be fighting traffic. And the best route I could find was far less than ideal. There was a 5-mile stretch of former country road, that is now used by commuter traffic. It was busy. It was narrow. It had no shoulder. And it was the least of all evils connecting the towns of Chapel Hill and Durham. Sure, I know about things like “ride big” and “take the lane”. I did those things. But as I watched in my rearview mirror for approaching traffic, it was a constant concern; would the car slow for me? Would I have to get out of the way? Statistics show that for slower-paced roads, concerns about being hit from the rear are overblown. That doesn’t change the basic human instinct to want to know what is going on behind, and not liking having a zillion cars whiz by. It is the number one reason more people don’t bike.

It just seems absolutely crazy that two neighboring college towns, Chapel Hill and Durham, don’t have a reasonable bike route connecting them. I blame this firmly on the old boy network in North Carolina’s DOT. Maybe I shouldn’t say this on a public blog, but those guys need to get their heads out of their rear ends and realize that we are in the 21st century, not the 1950’s. Maybe in the 1950’s we needed more roads to be built; now we don’t. Now, we need more bike paths, sidewalks, railways, and other means for people to get around without burning ridiculous amounts of energy. And doing this would benefit the drivers too – it is never fun for a cyclist to be passed by a bunch of cars on a narrow busy road. But it is no fun for the drivers, either. Building out infrastructure to appropriately accommodate both would make everyone’s lives better.

Would I do the trip to Durham/Duke again? Yes. It was great. Much better than sitting in a car or bus. I got exercise, and an adventure, all wrapped within some important work-related business. I would probably plan my ride for a bit less busy time, if possible. But, regardless of whether I would do it, most people just won’t face such a ride, without the kind of experience I have commuting by bike. And some people think I’m crazy, anyway. To get more people on their bikes, and less people using up tremendous amounts of energy to move metal boxes around, we need to invest in bike facilities, now.

Why isn’t that part of the economic stimulus?
(note: there are token amounts in the stimulus for bike paths, but they pale in comparison to road funds).