Harvesting energy from revolving doors

Remember the Matrix movie and the way humans became grown heat-producing plants to provide for their machine lords? The word “harvesting” gives me the crawls, but luckily harvesting in this world is for our own benefit and energy dependence. Interesting ideas so far are the energy harvesting from gym users or vibrations from trains and human steps. Kinetic energy is everywhere, it is just a matter of how to harness the damn thing and convert it to useful energy. However there are some nice opportunities where kinetic energy presents itself in more organised ways and can be collected more easily. Case in point is Fluxxlab’s revolving door harvester. It can be an all new installation or a conversion to an existing door. Unsuspecting humans rotate the spindle, that then rotates a magnetic wheel, that in turn creates current flow in stationary wire coils. Simple and effective.
It is very difficult for energy harvesting to become a large energy contributor. The revolving door concept is an elegant and admirable effort and I would love to see the wide commercialisation for this and similar ideas. As however practical and financial parameters play a dominant role, I will return on the harvesting issue with more comments and thoughts.

Link: Electronrun

Road energy system collects solar energy to heat buildings

Think of this system as a massive heat exchanger. Pipes underneath the asphalt carry water that is heated during the day from solar energy and then stored underground for later use. When the weather turns cold, this very same heated water forms the basis for the heating of buildings.
You think it’s a joke? Think better because a Dutch company called Ooms Avenhorn has already succesfully tested the system in a village and a military airport to heat buildings and a hangar respectively. And not only that, the hot water is also used in winter to keep the road ice free, while cold water stored for summer can be used equally effectively for cooling! According to Ooms, emissions are cut by half, while salt for the road becomes unecessary.
In fact the sytem involves absolutely nothing complicated, it is a matter of simple thermodynamics, measuring temperatures reliably, storing in places with good insulation and using the right pumps. And since there is enough heat absorbed in Holland, think of all the solar energy that could be collected from a road here in Greece! But since the local sport is digging roads to install or repair water/sewage pipes, electricity lines, telephony lines and God knows what else, I am not beting on seeing such a system here soon…
Link : Electronrun