hydroelectric powered, Solowheel Seattle, super efficient, super green -

How much does it cost to charge/fuel a Solowheel?

I am going to blow your mind. How much does it cost to fully charge a Solowheel in Seattle? Remember, a fully charged Solowheel gives you one hour of city riding and recharges in about an hour.

The answer: Under 2 cents to ride for an hour...using Seattle's 90% hydroelectric power!

Let me try to walk you through the energy numbers (thanks to Paul, a Seattle Solowheel rider and energy consultant):

So the rated energy stored is 122wHr= 0.122 kWhr. ( there are 1000 watts in every kilowatt). Seattle 2014 residential electric rates include a small per day charge (16 cents, which we can ignore as it will be small compared to total power used), a starting (first block) rate, and a final (last block) rate.  Solowheels would add to existing load so Its the last increment in the bill. Using just the higher last block rate of $0.116 /kWhr: 0.116 $/kWhr X  0.122 kWhr = 0.014 $/charge. That's the cost of the energy in the battery, which doesn't include charging inefficiency, losses, etc.  First guess at those would be 50% efficient (probably conservative, but simple for math), which doubles the cost to 2.8 cents.

One way to get better efficiency number is using the specs on the charger.  Output is 58.4 V x 1.5 A = 87.6 watts. That, with a charge time tells actual energy used to charge.  If it takes 2hrs (double the normal charge time), that's 87.6 x 2 = 175.2 watt-hours  (round to 0.18kwhr) used per full charge; 0.116 x 0.18 = 0.02 Or about two cents of power used to charge. That's a lot different in percentage terms from the first estimate, but less than a cent is not practically different!  We're in the same ballpark of a few cents per charge.  

As a Baby Boomer, you'll notice this is cheaper in absolute terms (no inflation) than a 1966 VW Beetle that bragged  "two penny's a mile!" (see video below)

What's enjoyable about this story is that I have a 1966 VW too!

And here is some more data on giving perspective on how efficient the wheel is:

 Hi Ted,
Reading about EUC's online,  I found your interview where you called Seattle traffic a 'bloodbath of energy waste' lol; I was wondering how energy efficient the Solowheel is so I calculated the numbers for a bunch of cars and compared against the Solowheel in "kwh per 100 miles". You may enjoy this :-)  -- the Solowheel Xtreme is 300 times more efficient than a Hummer, and about 32 times as efficient as a Nissan Leaf.

Battery Range Energy Efficiency
Car MPG kwh miles kwh/100mi
Hummer 2013 12 305
Subaru Forester AWD 2015 25 146
Prius 2012 50 73
Chevy volt 2014 16.5 38 43
Nissan Leaf 2013 24 75 32
Tesla S 85D (2014) 86 270 32
Solowheel Xtreme (2015) 0.155 15 1
Assume 36.6 kwh per gallon of gasoline, then calculate kwh/100mi as 3660/mpg.
See also:https://physics.ucsd.edu/do-the-math/2011/08/mpg-for-electric-cars

-- Daan