Nature’s Gentle Energy Can Power Billions
By Burt Hamner
Poor people living off the grid spend over $25 billion a year to charge their phones. New hydropower technology for harvesting free USB energy from nature could improve their lives.
The USB revolution is creating new opportunities for renewable energy solutions at the personal level. The economic opportunities for harvesting USB power from motion in nature are huge. But there are challenges facing the different technologies available today.
The Universal Serial Bus (USB) for micro-power is revolutionizing micro-electronics, and it’s not just a fad, it’s official. In 2009 the International Telecommunication Union (ITU) announced that it had embraced micro-USB as the Universal Charging Solution — its “energy-efficient one-charger-fits-all new mobile phone solution.” For the foreseeable future, all mobile phones will have USB charging systems. That is pushing all kinds of small electronics towards USB power. Besides communication, there are USB devices for navigation, education, data storage, and LED lighting. USB did not even exist before 1996. Now there are 10 billion USB devices looking to plug in. It is perhaps the biggest and fastest transformation of power systems in history.
USB power is tiny – the standard is 5 volts and between 0.25 and 2.0 amps of power, equal to 1 to 10 watts. Thus, USB power is delivered slowly – most of us have experienced the long wait for our phone to charge up. 2 hours minimum to fully charge by USB – it’s the “law.” When we have utility-grid electric power that’s always on and steady, waiting a while is not a concern. But this directly affects the feasibility and cost of USB charging systems powered by natural energy.
Millions of people work and play “off grid” away from utility grid electricity, and they are taking their USB-powered phones and GPS and LED lights with them. Over 1.2 billion people live off grid, almost all of them in poverty. Amazingly, over 700 million of them have mobile phones and have to charge them. According to the 2011 report, Global Green Power for Mobile Charging Choices: Mobile Phone Charging Solutions in the Developing World, these people pay between $1 and $7 a month to buy charges from local vendors who usually have car batteries with adapters for USB output. Assuming a global average of $3 a month times 700 million people, the world’s poorest people are spending over $25 billion a year to charge their phones.
Without car batteries, what choices do people off the grid have for USB charging power? Solar power is the most common solution. But solar panels for remote charging are still quite expensive. They retail in the US for more than $100, much more than billions of people can afford. And solar is slow. The batteries in solar chargers must have steady power for hours in order to charge. If it’s cloudy or rainy, they don’t charge. The comments of solar charger buyers on websites like Amazon are revealing – there are many very low ratings, almost always because the devices just don’t charge well when needed.
Thermo-electric power for charging is now available in some products like the BioLite stove. But the USB “law” of slow charging defeats this application in reality. The user has to feed the fire constantly, for at least two hours, to fully charge a typical smart phone. While there are many positive comments about products like this on vendor websites, the disappointing reality is discussed in extensive user reviews like this one.
Several USB chargers for bicycles are now available. The reviews are generally positive, but the cost is still high, and of course you must have a bicycle and ride it for many hours to get a charge. The rural poor don’t usually have bikes, and the urban poor usually have some access to power.
Hand-crank chargers or dynamos have been around for years. But again the law of slow charging makes them impractical for full charging and regular use. One reviewer on Amazon wrote that the hand-crank charger exhausted his arm after 10 minutes of turning, “and I’m a weightlifter!” He wrote that after getting only 5 minutes of power from his phone.
Wind seems a natural power source for charging but there appear to be only two companies making wind turbines specifically for USB power output. The Orange Wind Charger by Gotwind has been advertised for several years but is still not commercially available. A similar device is offered by a Hong Kong company, but no price information could be obtained from them. It should not be surprising there are few offerings. Wind is not a reliable power source in most places, especially close to the ground, and a small wind turbine typically needs wind speeds over 20 MPH to generate useful power. Even the smallest wind turbines designed for charging car batteries cost hundreds of dollars.
Now, my start-up company in Seattle is tapping into the other great renewable energy resource, hydropower, for USB charging. The Hydrobee (TM) is a turbine battery that is charged by water flowing at walking speed in a stream or river, or from a faucet or hose with standard household water pressure. It can also be towed behind a canoe or sailboat. Made from simple components, it is expected to cost half as much as solar panels with similar power output. It charges in 2 to 4 hours depending on water speed or pressure, and charges phones at their maximum charge speed.
This solves the problem of slow USB charging. Placed in a stream or river, the water flow steadily runs the turbine, which charges the internal batteries. Meanwhile, the owner does something else. Water flows are predictable, at least over weeks at a time. Even in dry regions, there are often irrigation canals that have enough water power to charge millions of USB devices.
In regions with household plumbing, which usually have electricity, the Hydrobee can provide power during blackouts. Attached to a faucet, it harvests energy whenever water is used for washing, cooking, or any other purpose. After Hurricane Sandy hit the US East Coast in 2012, over 10 million people had no electricity for weeks, but millions of them still had water pressure that could have charged Hydrobee turbines.
The founders of Hydrobee SPC, Dane Roth and I (Burt Hamner), designed and built large hydrokinetic turbines in our previous company, Hydrovolts, Inc. That company was sold to investors earlier this year, and we founded Hydrobee SPC to bring the new Hydrobee USB turbine to market.
We realized that the new world of USB charging does not need lots of power; it needs tiny power delivered steadily in billions of places. We are turning the concept of hydropower upside down. Instead of extracting the most hydropower possible from a particular site, we can harvest the minimum power from the most sites for the most people.
The Hydrobee turbine is being developed with support from backers on crowdfunding site Kickstarter. We hope to raise at least $48,000 to complete the engineering and testing of the Hydrobee turbine and bring it to market.
Our eyes are on the prize of 100 million people who live near streams and rivers and coastlines and need USB power. But we are going to market with campers and hikers and ‘preppers’ in developed countries, so we can establish the product. Then we will partner with global development agencies to help people in developing countries get the Hydrobee so they can save money and time on charging.
Kickstarter backers are suggesting other ways to spin the Hydrobee turbine battery –using bicycles, wind, even farm animals towing a little trailer with a gear box connecting the turbine. There is motion in nature all the time. I think we’ve hit on a solution of a universal USB energy harvester that can be operated with various attachments. We are starting with hydropower because it’s predictable, steady, and found all over the world. With initial success we can develop a line of charging accessories.
The market opportunity appears to be immense. Since $25 billion a year or more is spent by the rural poor to charge their phones, charging solutions that harvest nature’s free energy have a clear value proposition. Making them affordable is the big challenge. Hydrobee’s approach, using simple off-the-shelf components and a very common natural power source, is a promising solution to achieve that goal.
Other entrepreneurs will surely follow in their wake.
Help fund Hydrobee over on Kickstarter if you want to see this product succeed.
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The low power limitation on current USB connections is about to go away.Wikipedia http://en.wikipedia.org/wiki/USB_power#USB_Power_Delivery_specification:
“In July 2012 the USB Promoters Group announced the finalization of the USB Power Delivery (“PD”) specification, an extension that specifies using certified “PD aware” USB cables with standard USB type A/B
connectors to deliver up to 100 W of power at 20 V. For PD-aware cables with USB-micro B/AB connectors the maximum power supported is up to 60 W at 20 V, 36 W at 12 V and 10 W at 5 V.”
The device above is way overkill. I’d rather have something that I can wind manually for recharging, or a device that can generate recharging power as I walk. I don’t need to find streams so that I can charge.
Nothing new here!!