by Ben N on November 14, 2014


Just the other day, I got the latest copy of HOME POWER magazine in the mail. The cover article was about a DIY 6 Kilowatt system that is about 13 miles from my house. What I wasn’t expecting to learn from the article is how CHEAP solar can be!

I live in south-eastern Wisconsin. We are not known for great solar access, nor has the state government or utilities been particularly supportive of renewable energy. However, this article was great, because everything listed in it DIRECTLY applies to me! These articles usually have some lists of costs and components as well as solar charts.

The solar panels used on the project were from Helios, the same people from whom I got my 48V solar panel for EV charging. (Who are unfortunately now out of business. They manufactured in Milwaukee, just 30 miles from me!) The article also lists our area as having 4.52 daily average peak sun hours and being at 43.1 degrees north latitude.

Finally, the article also listed the total cost of the system, including available financial incentives. While Wisconsin has pretty minimal support for renewable energy, it does have one shining star – the Focus on Energy program. In this case, a $2,400 refund on a solar system. The one catch is that there is only so much money per year, so you have to get it before it runs out! (PS: It’s gone for 2014. But that’s OK, start a project in January!)

So, that got me thinking. What would it really take to put up a solar system to take care of me and my family?

bill_IMG_1204To start with, we need to know how much energy we already use. That’s pretty easy, just check the electric bill. Last month, we used 270Kwh. That’s less than a third of what the average American home uses, and frankly, it was a pretty good month for us. Our energy use has historically been a little higher than that, but I did also just recently refit the entire house with LED light bulbs and WAS expecting to see at least a little drop in electric use. (No joke, the other day, the power company stopped by to look at my meter, thinking it wasn’t working right!)

So, if I know how much energy I used (270 Kwh) and I know how much sun we get in my area (4.52 average peak per day,) then I can figure out how big of a system I would need to make that much energy. I thought I would run a test example based on a system exactly one-half of what the author of the article built. So, 3,000 watts (3Kw) times 4.52 (peak sun hours) times 30 (days in a month) is 3,000 x 4.52 x 30 = 406800 or 406.8 Kwh. That’s MORE than the 270 we used last month, and right around what I believe our new average will be.

I visited an online solar equipment seller and priced out 10 315 watt panels. They were right around a buck-a-watt, or $3100 for the set. Looking at grid-tie inverters in the 3Kw range, they were priced from $1500-$2000. So, for about five grand, I could have the main solar components, although I would still need cables, a disconnect, shipping, etc, which would of course add to the cost.

altE_kitWhile I was on that particular web page, I did see that they sold some solar “kits”. These include all the major components for a system, INCLUDING disconnects and the solar panel racking. One of the kits was for a 2.5KW grid-tie system using micro-inverters. The kit costs just under $6,000.

But wait! Let’s figure in what’s available for financial incentives in my area. There’s a federal tax CREDIT of %30 for solar systems (any excess on the tax bill can even be carried over to the next year!) and there’s that $2,400 refund through Focus on Energy. So….
-$1800 (30%)
-$2400 (Focus on Energy refund)
=$1800 final cost

What? Really?! I could basically never have to pay for electricity again (or burn any coal or nuclear fuel) for under two grand!?!? Yep, that’s right. Well, it does presume a few things. This would assume that I do the labor myself AND I already have an appropriate place for the panels. On top of that, I would still need to shell out some money for permits and to get an official qualified electrician to sign off on the project.

DSC_7210Keep in mind that physical space is also a major consideration for solar. You need a good sunny location, free of trees and other shadow-producers to make that kind of energy. Unfortunately, I have a narrow “double-deep” city-style lot that runs north and south, and a heavy tree-line from the neighbors. The ONLY legitimate location for solar at my house is on the roof of my garage. (The exception to that was mounting a 48V solar panel on a custom child’s playhouse to get it out of the shadow of the house!)

solar_chickenscratchings_IMG_1203The garage itself is a a little over 20-foot square. Will that many solar panels even FIT on my roof?! Those 250-watt Kyocera panels measure 66 inches high by 39 inches wide. So, a configuration of five-wide by two panels tall would be 16.25 feet wide by almost 11 feet high. 16 feet is less than the 20 foot width of the building. Running Pythagoras’ theorem on a 12/12 pitch roof of a 20′ square building comes up with a roof height of just over 14 feet. The solar panels wouldn’t just fit on the roof, they would fill it nicely, and LOOK GOOD!

So, solar power for the cost of an old used car? AND it fits on my roof? Sign me up! Even going with a 2.5K system instead of a 3K, I’d still be averaging 339 Kwh per month. Again, more energy than I used last month, although probably a little under our monthly average use. Using the slightly larger Solar World 315 watt panels would get me to right about my average energy use.

Some people like to think about things solely in terms of financial return on investment. If so, how would this theoretical solar system stack up?  Well, it would save me $40 a month on my bill. At a cost of $2000, it would pay for itself in 50 months, or just over four years. Every month after that, it’s like I’d be getting paid $40. (Although I’d still have to pay the $6 monthly meter fee!)

So, does solar energy cost a lot of money? Think again, it might not cost what you think!

Stay charged up!


PS: Am I going to run out and buy a system right now? Sadly, no. My garage is very old, and the roof faces east/west instead of north/south. I intend to rebuild it anyways, and since I will, I’ll design it specifically with a south-facing 45-degree roof. Needless to say, I won’t have a “real” solar setup until after dealing with lot lines, permits, and building plan meetings…..

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Motorcycle NiMH battery pack upgrade –

by Ben N on October 29, 2014

Two weeks ago, I got started on my electric motorcycle battery pack upgrade by tearing apart a Ford Escape Hybrid battery pack.

After that, I was trying to figure out the best way to repack the cells into a size and shape appropriate for the motorcycle. Since I already had the original black plastic battery tray material from the Escape pack, I tried reusing that, cutting it to the size needed.

While working on that, I noticed a few things. One was that there are two different sizes of bus bars used in the pack. That accounts for the fact that every couple of rows of cells, there’s some additional spacing for the bolts that go through and hold the entire pack together. That means that I won’t be able to use an even spacing of the cells in my motorcycle pack design.

Also, the plastic that makes up the original battery tray is really terrible stuff. It’s brittle, smelly, and impossible to cut straight. After making a few cuts to try to create a smaller pack, I also found out that the material is less symmetrical than I thought it was. That means that bolt holes from one piece will NOT line up with those from another.

Back to the drawing board, I’ve seen cylindrical cells mounted through sheet plastic with round holes cut in it. Would this work for my project? Who knows? The only way to find out is to try it. I measured the diameter of one of the cells, and then drew that as a circle on a computer drawing program. I duplicated it 47 more times, trying to arrange it to fit inside the rough shape of the motorcycle frame. That done, I saved the file and took it over to a friend who has a laser-cutter. We put some scrap cardboard in the cutter and used it to carve the holes out of the cardboard.

I arranged the cells through the cardboard template inside a milk-crate (to hold the weight) and saw how the cells were spaced out. Overall, it looked like it should work fine, although without the cardboard templates connected to each other, the entire array was floppy and difficult to work with.

Of course, I really can’t do any EXACT work on the size and shape of the NiMH battery pack without getting good measurements of the inside of the motorcycle frame. And that’s rather hard to do with the existing Optima YellowTops. It was time for them to come out. I set to work taking off the tank, removing the top tie-downs, followed by the electric connections.

After removing the top two batteries, I noticed that I had forgotten how the middle part of the rack also supported the plate that holds the controller, main contractor, fuse, and other important components. I’ll have to support this in some other way when I get the new battery pack in. I removed the bolts going from the middle section of rack to the frame, and was able to get the middle section out.

After that, it was just a matter of disconnecting the power cables on the bottom two batteries before removing them from the frame.

At this point, I now have an electric motorcycle with NO BATTERIES in it. The only thing I can really tell you so far is that it’s considerably lighter and easier to push without battery weight.

So, what’s my next step? Hmmmm. I’m thinking that perhaps I just actually set the cells right down on the bottom of the bike frame. I don’t think it would be too hard to connect them with the bus bars to make a small pack. I could even space out the cells with just some foam or scrap wood for now. A block of cells could be strapped right down to the frame for temporary testing. The next trouble that I see is creating bus bars or cables for connecting the columns of cells together. In the Ford Escape Hybrid, the cells were only in two layers. In the cycle, it’s likely going to be 12 layers high! That’s going to mean MANY more vertical connections – ones that I don’t have bus bars from the Ford battery pack for.


Super-Heros ride electric motorcycles

by Ben N on October 23, 2014


Super-Heros ride electric motorcycles, and so can you.

This summer, I was able to attend the official release of the Harley “Project LIVEWIRE” electric motorcycle at the Harley-Davidson Museum in Milwaukee, Wisconsin. With the crowd cleared from the street, the electric motorcycle ZOOMED up to the museum FAST with a distinct electric motor whine.

To me, that’s the sound of the future, what a motorcycle SHOULD sound like. Of course, one of my first motorcycle memories was watching the Light Cycles in TRON at a drive-in theater. Thirty years later, we finally have REAL (unlike TRON’s computer animated) electric motorcycles, and the Harley is going to be shown off in a big way in the Marvel’s upcoming AVENGERS: AGE OF ULTRON.

A little while back, I saw some sneaked photos from the set, that were highlighting the actors, but what I noticed was the Harley Livewire. Since the AVENGERS preview came out yesterday, we can finally see the LIVEWIRE in action.

Here’s some screen-grabs from 1:27 and 1:34 that feature the cycle. Black Widow launches from an airplane KNIGHTRIDER-style, followed by Captain America doing some slo-mo drifting at 1:34.widow_128 captain_america_134

For me, movies have always been the land of imagination, where the fictional becomes real. TRON really was the inspiration for me to build my own electric motorcycle.

tron_yellow-and_blueNow, we instead are getting not just “product placement” in movies, but clever nods to the real world as well. (I was the only one in the theater who laughed at the joke of Elon Musk’s cameo in IRON MAN 2.) In reality, we’ve had some good electric motorcycles for a while, with Brammo and Zero topping the list. Even electric scooters are going mainstream.

But, if Black Widow or Captain America riding an electric motorcycle gets somebody excited about E.V. two-wheelers, I’m all for it!

I may not be a super-hero, but I gotta say that building your own vehicle and then hitting the road with no engine noise and instant torque is about as close it it comes to being super-human. Not bad for a kid who has seen too many movies.

Batteries to power, turbines to speed. And don’t forget the popcorn.



PS: I’ve also spotted the Tesla Model S several times on the current television version of Green Arrow.



A while back, I ended up at a salvage yard a few hours drive from my house. While I was there to get a transmission, I also ended up walking away with a Ford Escape Hybrid battery pack.

The battery came out of a truck that had been rear-ended, and there was a bit of a dent in the back of the battery case, but not bad. For $150, it was worth it for me to buy the pack and take it home.

So, the hybrid battery has been in my garage since then, just waiting for the right time for me to crack it open and pull out the cells. Theorically, this battery pack has 300 volts at 5.5AH, or about a 1.6KWH capacity. Not huge, but most hybrids use are constantly charging and discharging their battery to best overall vehicle efficiency. I figured that if I pulled out the cells and re-packed them, I could create a lower voltage pack at a higher AH capacity.

DSC_3218So, I set to work taking the pack apart. (Warning: Many battery packs are 300V+DC and potentially FATAL electric shock hazard. Kids, don’t try this at home!)

First, I removed the top cover. Pretty easy, just LOTS of bolts to take out. A power screw driver comes in handy here.

Next, I pulled out all the bolts holding on the black plastic cover over the cells. The larger bolts were very long and went all the way through the pack and into the bottom of the housing.

I was able to grab the part of the pack that held the cells and shake it a little. It was mostly loose, but still held in by connections at the service disconnect and main contractor. I also removed the cables going to the cooling fans and the physical connections of the ducts to the cooling fans. I was extra cautious working around both the service disconnect and main contractor. The cables to them are always color-coded orange, indicating high voltage wiring, typically in the neighborhood of 300V.

The cells are actually arranged in two layers, an upper and a lower. The service disconnect is between the two. So, when you disconnect the battery pack, you not only break the circuit, but also make the battery into TWO 150V battery packs, instead of one 300V pack.

DSC_3231With the service disconnect and main contractor both disconnected, I pried on the upper block of cells, and had several pieces of oak firewood handy to use as spacers to set the cells back down onto. This would give me a way to get a good grip on the block of cells and also see what other wiring might remain and need to be unplugged.

After disconnecting a few more wires, I was really to remove the upper block of cells. (Lift with the legs not the back…)
OOOOOOOOmmmmmmfmmffff! I got the cell block out and carried it over to a pair of saw-horses, where I would have better light and more room to work.

On top of the cells was an array of sensors – temperature sensors and a large circuit board for cell management, held in by about a zillion screws. I set to work removing them. I also tested the block of cells with my volt-meter and found that this half of the pack was at about 166 volts, which sounded about right for a full charge.

I removed the BMS and then trim covers on both ends of the pack. Those with the cell connections. I used the multimeter to test and saw that they were connected in a serpentine pattern so that each electrical connection was about 24 volts higher than the previous one. I removed those interconnect bolts, which finally brought the pack down from a 150V+ down to a mere pile of 6v components.

DSC_3234The cells in the pack are Sanyo NiMH “D” cells, with 5 connected in series to make 6V sticks. The entire battery pack is composed of 50 of these 6V sticks.

I checked the polarity of each with my multimeter and then marked the Negative end (-) with a black Sharpie marker. Then I pulled them out, one at a time, and stacked the sticks, all pointing the same direction.

Once I had this all figured out on the first half of the pack, I pulled out the lower layer of cells and did the same, carefully stripping out the cells.

Next, I took a look at the area on my motorcycle taken up by the lead-acid battery pack. Essentially, it was a rectangle that was 14 inches wide, 17 inches tall, and 7 inches across on the bottom. (The batteries are a different orientation on the bottom vs the top of the pack, but I’m just going with the smaller size, figuring I want the NiHM cells to be packed as a rectangle.

The NiHM cell sticks are over 13 inches long including the terminals. 14 inches is probably about right for a little space to work around them. I packed the cells into a milk crate in a 4 x 12 grid. That would mean that every two rows of four is 8 sticks (which makes 48V) and it would be 6 of those groups of 8 sticks in parallel to make the entire 48V pack for the motorcycle.

DSC_3262Next, I’ll have to figure out how to mount all the cells together. I’m thinking about laser-cutting circles in acrylic to make a clear case where all the cells would just slide through the holes to make an array. I’m not sure how much heat will be made during charge and discharge, so allowing an air-gap between the cells and adding something like a computer fan might be a good idea. I’ll probably base the spacing of the cells on reusing the bus-bar interconnects from the Escape Hybrid battery pack.

That’s it for now. I am showing off my motorcycle at an alternative-fueled vehicle day two days from now. Maybe after that, I’ll pull the lead-acid pack, to be able to take some real measurements for the NiHM cells.

Til next time, stay charged up!




Electric Motorcycle DVD Now Streaming!

by Ben N on September 22, 2014

motorcycle vimeo promo

Recently, I’ve had some requests for a STREAMING version of BUILD YOUR OWN ELECTRIC MOTORCYCLE. Frankly, there’s some parts of the world where the mail service is so bad, I simply CAN’T mail a DVD, as it just won’t get there. Also, I’m starting to find some folks who don’t have televisions or DVD players, just a laptop computer (or tablet) that won’t have a DVD drive.

So, I started looking around for what services are out there for a film-maker to release their project through. After a little searching, I decided to go with Vimeo’s On-Demand service.

So, I spent the time do a re-edit of the instructional DVD to create a “feature film” version and upload it. I originally shot all the footage in high-definition, so I’m now able to release it as an HD Film!

I really hope that folks appreciate the message and this makes it that much easier to get the word out showing how anyone can build their own electric motorcycle!

Please take a look and let us know what you think!

-Ben Nelson