ChargeCycle
Generating Electricity Through Pedal Power
Designed by: Jamie Young, Aaron Oro, Jeff Sarsona, Chuck Allen
Addressing a Problem
• Clean and green energy is demanded around the world today
• Second and third world countries are also without a cheap and accessible electricity
• Our group’s principal goal is to provide energy to communities without electricity or
a consistent source of light
Method for Accomplishment
•We could take two approaches to accomplish this goal:
➡ Introduce a new product or service and hope that it succeeds in front of a new
audience
➡ Innovate on an existing technology or service, reducing the need for product
education. The latter option appears more practical and feasible to achieve.
Initial ideas
Target Areas
•
In examining target areas, our group recognized a need in India and China for
electricity. We also recognized the use of bicycles in Western Europe and the US.
•
•
Bicycles serve as a main method of transportation in these countries.
Over 60% of India’s population already owns a bicycle
Applying Product to Place
•
•
•
Attempt to create a product that can be attached to a bicycle.
At its base level would be able to generate enough electricity to charge two AA
batteries by harnessing the mechanical energy of pedaling.
This electricity generation would occur during transit, providing an effective and
accessible method to produce electricity for needy communities.
Existing Bicycle Generators
•
•
The majority of bicycle generators today are stationary bicycle generators
manufactured by Windstream, Convergence Tech and Magnificent Revolution
Typical design includes a back-wheel stand that elevates the bicycle and causes the
back wheel to come in contact with a smaller wheel that is hooked up to a “bicycle
dynamo” and a large battery
•
Flaws Include:
➡
Significant amount of energy is lost to
friction
➡
Heat energy is lost during the electrical
conversion and storage to the main battery
pack
➡
A stationary bicycle generator is stationary
and does not allow for the user to produce
electricity while traveling on his or her
bicycle
➡
Typically priced around $500
Existing Bicycle Generators
•
•
•
•
•
A few companies have produced
bicycle generators that can be used
while biking
Bike2Power and Nokia have come
out with similar models relying on a
bicycle dynamo whose axle rubs
and spins with the rotation of the
front wheel
Both products are priced around $80
More recently, ECOXPOWER
released a product that uses the
rotation of the spokes in the bicycle
wheel to generate electricity
ECOXPOWER is priced at $99.99
Observed Flaws
Flaws with Bike2Power and Nokia design:
➡ The rubbing of the dynamo against the wheel causes a lot of friction (which could,
among other problems, wear out the tire)
➡ The rubbing of the dynamo is an unnecessary loss of energy to heat
➡ The rubbing of the dynamo restricts the movement of the bicycle because the
dynamo acts as a sort of brake
• Flaws with ECOXPOWER design:
➡ The price is heavy and not easily affordable
➡ Because of the technology that the product employs, the durability of the device is
questionable
Analyzing Existing Products
•
Based on the observed flaws with existing designs, ChargeCycle’s design will
attempt to accomplish:
➡
Allow the user to generate electricity while traveling on his or her bicycle
➡
Eliminate inefficient energy production (i.e. energy lost to friction and heat)
➡
Be cost effective in order to access a wide market
➡
Be durable in order to also be more cost effective and user friendly
How to Harness Energy
•
•
Wanted to make use of the pre-existing motion of the bicycle, so we looked at
specific areas of the bike - the wheels and the pedals - trying to find a way of
tapping into the rotational motion.
As shown below in Figure 1, A is an ideal location for placing a custom gear, which
could transfer power to the generator via chain or belt.
!
Circumference Data
•
•
We gathered data about the circumference of A in Figure 1 from the bicycles on the
Stanford University campus
Sampled 99 bicycles
•
~50% had a circumference of 2 ! inch, and another ~40% only varied by +/- 1/16
!
ChargeCycle Design Thinking
•
•
Create a removable gear which would clamp on to the space between the main bike
frame and the pedal shaft (space A in Figure 1)
This larger gear would be connected to a smaller gear higher up the bicycle
•
•
A metal axle would run through the center of this smaller gear
Therefore, as one pedals on the bicycle, the metal axle would spin
•
•
Using a system of gears, the axle would spin a DC generator, producing electricity
The generator would be electrically wired to a USB hub
ChargeCycle Design Thinking
ChargeCycle Design Thinking
!
Testing the Design Thinking
•
•
Decided to prototype our design by creating a “proof of concept” prototype
The general idea of the prototype is to illustrate that energy can be produced
through our mechanism and feasibly charge our desired devices
•
Our design for Prototype #1 was very different than our ideal design; however, this
was mostly based on the fact that we didn’t have time to manufacture our
specialized parts
Prototype #1 Drawings
Below is a detailed sketch of the ChargeCycle Prototype #1 design.
Prototype #1 CAD Drawings
Below is a series of CAD drawings of the ChargeCycle Prototype #1 design.
Prototype #1 Results
In order to prove basic functionality, our team decided to prototype a version of the
design using scrap parts and a variety of random parts found at hardware stores.
Electronics
• Alexander Dewing
• Just look at that
winning smile!
Prototype #1 Demonstration
Planetary Gear System
A depiction of the planetary gear system, an essential piece to electricity generation.
The Ideal Design
The ideal removable, adjustable main gear system that connects to the bike axle.
The Ideal Design
The ideal main connection system that provides electricity through a DC generator.
Partnership and Business
•
•
We won’t sell directly to consumers (these will be the people in China and India)
Use a “middle man” such as a government or a non-governmental organizations
•
We will take this approach for a couple of reasons:
➡
NGOs and governments already provide the infrastructure to get a product to a
consumer
➡
It would be much easier to implement and spread a product through an
established NGO or government action.
The Future
•
•
Tailoring a product to the needs of specific region is essential for gaining traction in
a target market
Evolving the ChargeCycle design to incorporate a USB hub to power a cell phone or
more advanced technology could be essential to the development of the product