In mid-May the folks at SunPower invited us to attend a major Silicon Valley bike-to-work day event held at the SunPower campus in San Jose. The afternoon promised to be full of dignitaries and biking enthusiasts. Russ and I looked at each other and realized that after years of tinkering and test rides this SunPower bike-to-work day would really be the first public debut of our little machine.

There was an awful lot to do to get ready. Our video camera to read the Outback charge controller was swamped by too much sunshine. We needed to finish wiring up the power supply for our stoker-to-captain communicator. An important shade panel over the stoker’s seat had to be cut and mounted. Both front and rear derailleurs had to be re-adjusted after we had earlier dismantled them. And we had to figure out how we could mount a special protective chain guard to the rear crank so that we didn’t accidentally shred the foot of some Silicon Valley dignitary.

But more bothersome was the dreadful surprise we got one week before we were set to take the bike to San Jose. All along our plan had been to rent one of those 6’ x 12’ enclosed trailers from U-Haul and tow it behind my Ford Explorer. We’d even designed the bike and solar trailer so that it wouldn’t be larger than the magic 11’ 7” interior length of the trailer. With careful alignment we figured we could nest the bike and trailer side-by-side inside the U-Haul, lash both down and be off and running to exhibits like the one at SunPower.

Imagine our shock when the U-Haul guy told us that his company wouldn’t rent its enclosed cargo trailers to be towed by, of all things, my Ford Explorer. I had towed a 2,000-pound popup tent trailer with the very same vehicle for years with no problem. Now we were trying to tow about 450 pounds of payload in an otherwise-empty trailer and U-Haul wouldn’t allow it. Turns out, the manager explained, someone once overfilled a U-Haul cargo trailer and while speeding in a Ford Explorer overturned and there was a fatility. After the ensuing lawsuits were settled, U-Haul, a strange privately-held firm, made the corporate decision not to rent its cargo trailers to those using Ford Explorers. Oddly enough they would rent to the same vehicle if it had the Navajo designation. The lawyers had won. We had one week to figure out how to get the solar touring bike the 120 miles from Sacramento to San Jose.

I briefly thought we could just buy an enclosed cargo trailer of our own, but I soon discovered that ones of the size we needed sold for $4,000 and more, even used. More than we were willing to spend on our out-of-pocket project. As the bike-to-work day got nearer, I cruised Craig’s List for some wheeled device which we could use. I learned about the universe of ‘toy haulers,’ designed to carry ATVs, motorcycles quads and all manner of recreational things. Amazing trailers, some even with living quarters above, with amazing prices as well.

At the last moment up popped an old 6’ by 12’ flatbed landscaper’s trailer, the ones you see gardeners using. It was perfect, especially because its 5’ rear gate could be used as a loading ramp. And at $600 it was a steal, with new tires, axles and bearings.

The day before the event we drilled some I-bolts into the floor, padded some contact points and carefully loaded the bike and trailer onboard. Would it fit? To our horror we discovered that the actual size of the flatbed was about half a foot smaller in all dimensions than the 6’ by 12’ we had assumed it was. We did some careful geometry, though, and found a way we could load the bike and trailer onboard. With the trailer and bike noses protruding a bit off the front of the trailer we slowly closed the back gate. We were amazed. There was just two fingers’ width of clearance. We were home free.

I was a bit leery if we could safely tow the whole rig at 60 mph with the large solar cell area open to the wind. Would the trailer become unstable? Would it rattle things loose? We had, after all, designed the bike and trailer for our nominal 20 mph cruise speed. But Russ was more sanguine. He’d towed bikes, canoes, kayaks and all manner of things on his Subaru roof. Everything was possible with enough lashing.

So we loaded up the trailer with precisely 11 straps, each one with a 2,000-pound working capacity. “That should be sufficient,” Russell said. And it was. We have a certain adjective we use on this project whenever we want something fastened down to absurd tightness. Things are ‘Russellized’ in this manner. I see it all the time. After he’ll borrow my toothpaste I’ll need a vice-grip to remove the cap. Same thing with anything else that turns, like a spigot or a butterfly nut. Now with the 11 1-ton straps the precious solar cargo was lashed down and ready for the road. The wheels would fly off before our solar bike.

trailered up rear

Our improvised trailer transport system worked beautifully.

Our improvised trailer transport system worked beautifully.


The trailer and bike towed like a dream. We were in San Jose ahead of schedule, and Russell’s strap design was so good that in ten minutes from our arrival we had rolled off the bike and solar trailer, connected the electrical systems and were ready to go. As we did a test ride around the SunPower parking lot we realized that something was making a repeating loud grinding noise. It turned out to be the protective foot disk we’d installed on the stoker crank, just a bit too close to the motor drive chain when under drive. It made our sleek quiet machine sound like an embarrassing squeaky shopping cart. We scoured our toolbox for something we could press into service to fix the scraping sound and we found that a strategic bit of electrical tape would quiet the racket…or at least until we got back home to make the proper fix. Five minutes later we were again whooshing along silently.

As we cycled in the noon sunshine we realized that the SunPower panels had finally made it back to where they had originated in 2008. We heard employees chuckle to see the very panels they had been installing on rooftops now zipping along on our strange contraption. We got lots of hi-fives and laughter. We also got stuck in a small hill of newly-plowed dirt we had tried to cross to get to the event. SunPower employees helped push our bike backward onto the blacktop so we could take our place just next to the main stage.

Our bike’s first public debut at the SunPower San Jose headquarters.  We were at the green tech ground zero, admired by CEOs and  tycoons.  We had a blast.

Our bike’s first public debut at the SunPower San Jose headquarters. We were at the green tech ground zero, admired by CEOs and tycoons. We had a blast.

Soon we met Bobby Ram, the first SunPower executive we came to know, an early believer in our project. Bobby was delighted to see our recent improvements in the bike and trailer and he soon was bringing other executives over to have a look.

SunPower Vice-President Bobby Ram  sits at the controls of our bike.

SunPower Vice-President Bobby Ram sits at the controls of our bike.

We spent a good amount of time chatting with San Jose Mayor Chuck Reed, a strong supporter of the development of alternative energy. Mayor Reed asked us some technical questions about the motors and energy budget for the bike and was very upbeat about the prospects for solar electricity in San Jose, the nation’s 10th largest city.

San Jose Mayor Chuck Reed talks about solar energy with Russ and Bryan.

San Jose Mayor Chuck Reed talks about solar energy with Russ and Bryan.

Because Silicon Valley has one of the world’s largest concentrations of green technology companies it wasn’t surprising how upbeat Mayor Reed is on renewable energy. His top ten goals in the next 15 years are impressive indeed. Here they are:
Green Vision Goals
Within 15 years, the City of San José in tandem with its residents and businesses will:
1. Create 25,000 Clean Tech jobs as the World Center of Clean Tech Innovation
2. Reduce per capita energy use by 50 percent
3. Receive 100 percent of our electrical power from clean renewable sources
4. Build or retrofit 50 million square feet of green buildings
5. Divert 100 percent of the waste from our landfill and convert waste to energy
6. Recycle or beneficially reuse 100 percent of our wastewater (100 million gallons per day)
7. Adopt a General Plan with measurable standards for sustainable development
8. Ensure that 100 percent of public fleet vehicles run on alternative fuels
9. Plant 100,000 new trees and replace 100 percent of our streetlights with smart, zero-emission lighting
10. Create 100 miles of interconnected trails

Mayor Reed wasn’t the only visionary executive at the bike-to-work day. Tom Werner, SunPower’s CEO, spent time examining our bike with his company’s donated solar panels. Werner is a huge bicycling enthusiast, regularly riding to work and staying fit. As he looked over the bike I thought of a challenge. “Hey Tom,” I asked, “Would you be willing to race against our bike and your own solar panels?” He paused for a moment and then asked, “What’s your top speed?” When I told him 22 mph he chuckled and told us he didn’t think he could outlast his own panels. We agree. In strong sunlight our panels produce the power of three Lance Armstrongs, an unfair advantage against a lone CEO. We took this opportunity to thank the entire SunPower team for their support and enthusiasm.

SunPower CEO Tom Werner,(l)  an avid cyclist, admires his firm’s panels on the solar touring bike – but gamely declined to race against us.

SunPower CEO Tom Werner,(l) an avid cyclist, admires his firm’s panels on the solar touring bike – but gamely declined to race against us.

After all the speeches, after all the questions and answers when the crowd thinned out and went back to work, Russ and I took a quick quiet ride in the neighborhood just to enjoy the pleasure of it. The bike was smooth, the weather perfect. We’d designed a way to take our little machine to shows and exhibits, important because in just two weeks we were set to spend a long weekend showing off what we made for 80,000 attendees at the Bay Area Maker Fair.

902 Responses to “SUNPOWER BIKE-TO-WORK DAY”

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