Good Grief, there are a lot of liberal sociologists around!
Using a stationary bike to charge batteries is quite an interesting application, and in some parts of the world it could be a zero-pollution means of providing power to enhance a towns quality of life. The large challenge is to have the greatest efficiency so as to obtain the most KVA for the effort put forth. The difference between bike power and small wind turbine power is that bike power is far more steady in most instances. The more important question is about what sort of low-speed generator or alternator could be produced that does not need multiple stages of speed step-up? Is there an efficient generator that runs at 50 RPM?
Glad to see someone put numbers on this. However, there is an error that is big enough that a correction is in order.
A "food" Calorie is 1000 "small" calories, so in fact the power in this estimate is 1000x too low.
After that correction, the estimate becomes 1 kWh produced by the cyclist, now perhaps Brazil can get their rice paid back. Especially if you consider that rice gets much heavier when cooked.
Regarding the question of cutting your bill by pedaling, a simple check is that a reasonably fit cyclist can generate something like 100-200 Watts. Assuming no conversion loss, that means 5-10 hours of pedaling for a 20-cent kWH. I love biking, but I guess I won't be doing it for the payback. Truly, we in the U.S. have cheap energy, for better or worse.
will this correct their attitude make them fit among the society? i feel 50% yes and 50% no. I have seen prisoners do carpentry work and generate money .When their time comes for regular life most of the money earned by them given to them to set their fresh life and a few self employment opportunities are also provided to start with.
-Cont- To use early release on prisoners is like using food to influence the starving and reinforces systems that can be gamed or are rigged. Then there is the vindictive mentality that anything done to prisoners is justified, because they broke some “law”. Remember (i.e. WWII), laws can be made to put anyone in prison and when the shoe is on the other foot, fairness in punishments becomes everyone’s concern.
There are potential problems with this pedaling punishment. Back in the early 1800’s some US prisons had man sized wheels where prisoners would for hours turn the wheel as hard labor for their crimes. This, along with isolation, many times resulted in insane “rehabilitated” people who were then released back into society to function. It also smacks of a decaying/backwards society (i.e. power pedaling used in the movie, Soylent Green). Then there is the make work nature where batteries are transported. The economical place, if any, to use the power is at the prison. Now there is the punishment aspect. In most modern societies, Incarceration is deemed the greatest punishment. To tack on little punishments here and there at prisons that are not monitored or controlled by the courts could lead to cruel and unusual punishments. Then there is the nature of punishment for all concerned. Correctly punishing criminals for their crimes is a potential deterrent to them and the cost to punish criminals correctly is also a potential deterrent to society. To find ways to reduce costs or create profits from criminals could provide a perverse incentive in a society. The proper way to do this is set up the bikes in a versatile exercise room for voluntary use by the prisoners to keep them healthy. If the prison can harvest that energy to drive their power needs then that is efficiency and not profit. Then the incentive to earn an early release must be connected to something positive for all sides, such as for a few hours a week in the gym to stay healthy rather than the power generated removes perverse incentives and promotes healthy prisoners who can better handle work after their release thus potentially reducing recidivism. More-
Re "Imagine the day when your morning ride could heat the stove for breakfast or your after work stress-reliever workout could power your TV."...
Or how about your morning ride delivers you into work and your after-work stress-reliever workout transports your body home, thus saving gasoline costs?
Oh wait, that's what my rides already do!
Lets fix the ideas. Assuming a prisoner eats 500g of cooked rice per day (huge quantity, very chip food), that accounts for ~1750 Calories per day, that is barely 7kJoules. Let's suppose the guy so good that the 50% of his energy can be transformed into mechnical power (the rest is needed for life functions) and no leak from the generator. So 3.5 KJ (overall available energy) could be all liberated in 1 hour to make ~1 Wh overal power. Now, the current price of rice in Brazil (raw, not considering transporation and cooking), is ~0.5$/Kg, that makes 25 cents of food per day to the future winner of the Tour de France. So brazilian government would depense at least 25c for 1 Wh, that is 250$/kW. No way to get more if the guy is not eating more. Now, that is are 3 order of magnitude vs. actual avg energy prize in US (less than 20 c/kiloWh-don't know in Brazil). The name of the game is not ''generated power'', but ''dissipated power from the convict'': we have interest that a young brazilian convict could to dissipate his eccess energy, while bringing him out to hammer some stone would be too costly. So better find a dissipating activity indoor, and give a bit of motivation. Actually you ask them just to ped, not to keep 25km/h on an high-load resistance, minimum heart attack risk. You compensate for their time, not for their power.
Conclusion: the title of the article ''Prisoners made to pedal for power'' should maybe be interpreted as "Prisoners made to pedal to dissipate their power'', that is no novelty in aprison environment.
in regards the first preposition (if i have understood correctly) understood......time duration of sentence remains the same... what is implemented is forced output, in positive (read wider community support) essence : benefit starts from the bottom. full stop.
What are the engineering and design challenges in creating successful IoT devices? These devices are usually small, resource-constrained electronics designed to sense, collect, send, and/or interpret data. Some of the devices need to be smart enough to act upon data in real time, 24/7. Are the design challenges the same as with embedded systems, but with a little developer- and IT-skills added in? What do engineers need to know? Rick Merritt talks with two experts about the tools and best options for designing IoT devices in 2016. Specifically the guests will discuss sensors, security, and lessons from IoT deployments.