My lawn is a solar collector. Energy is stored in the plant material, and it can be harvested after the lawn is mowed by firing the clippings in a combustor to generate heat or power. A more efficient use of this energy, however, is to recycle the clippings back into the lawn or into a garden as compost to offset petroleum-based fertilizer.
Perhaps the most environmentally benign option would have been a manual reel mower. However, I wanted to be able to mulch the clippings or collect them for composting as I desired. Plus, my reading suggested that manual reel mowers don’t handle weeds well, and my lawn has a pretty serious weed problem.
When I was a kid, one of my household chores was mowing the lawn with our gas mower. I remember jerking on the starter cord a dozen times to get the engine to turn over, inhaling exhaust fumes, being deafened by the engine roar, and having my hands vibrated so severely that I couldn’t feel my fingers. I also remember running out of gas and having to fill up the mower from the fuel can we kept in the garage. I hated mowing the lawn.
The cordless mower is a totally different experience. It is quiet and smooth. The engine easily turns on and off with a spring-actuated lever – no starter chord. At 76 pounds, the CMM1200 is a bit heavier than push gas mowers in its class (which usually run under 70 pounds) due to its 24-volt battery. However, it cuts grass just as well as its fossil-fuel-fired cousins, and frankly I need the exercise.
Of course, so long as the mower is recharging from a wall outlet, it is not truly using renewable energy. However, what sets cordless electric mowers apart from their plug-in counterparts is that the recharging station can be modified to use any electricity source, including solar power. Thus, as a long-term project, I plan to build a solar-powered charging station to make my cordless electric mower truly renewable. However, I will probably wait until the manufacturer’s warranty expires before attempting such a retrofit.
Advertised as the "Most Powerful Tablet Under $100," the Kindle Fire HD 6 was too tempting for the team at iFixit to pass up. Join us to find out if inexpensive means cheap, irreparable, or just down right economical. It's teardown time!
The increased adoption of wireless technology for mission-critical applications has revved up the global market for dynamic electronic general purpose (GP) test equipment. As the link between cloud networks and devices -- smartphones, tablets, and notebooks -- results in more complex devices under test, the demand for radio frequency test equipment is starting to intensify.
Much of the research on lithium-ion batteries is focused on how to make the batteries charge more quickly and last longer than they currently do, work that would significantly improve the experience of mobile device users, as well EV and hybrid car drivers. Researchers in Singapore have come up with what seems like the best solution so far -- a battery that can recharge itself in mere minutes and has a potential lifespan of 20 years.
Some humanoid walking robots are also good at running, balancing, and coordinated movements in group settings. Several of our sports robots have won regional or worldwide acclaim in the RoboCup soccer World Cup, or FIRST Robotics competitions. Others include the world's first hockey-playing robot and a trash-talking Scrabble player.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.