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WKetel

8/2/2012 6:06 PM EDT

Good Grief, there are a lot of liberal sociologists around!
Using a ...

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seaEE

7/27/2012 10:45 PM EDT

I like the idea of prisoners doing some work that benefits society, but somehow ...

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Prisoners made to pedal for power

Leslie Langan

7/23/2012 1:47 PM EDT

At the Santa Rita do Sapucaí Penitentiary in Brazil, prisoners have been given the opportunity to shorten their jail sentence by becoming human power generators.

The initiative is centered around two stationary exercise bikes, placed in the courtyard of the penitentiary. The bikes are connected to batteries which can be charged using the cyclists’ kinetic energy.

Once charged, the batteries are transported to the city where they are used to power the city’s street lamps.

For every 16 hours of pedaling, prisoners reduce their total prison sentence by a day.

One day of cycling can power up to six light bulbs, and it’s thought that if the program were to be scaled up, it could produce enough energy to power the entire city’s street lights.

Pending an improvement in the total power harnessed per hour, this human powered method of producing green energy could change the way people around the world choose to get “off the grid”.



Imagine the day when your morning ride could heat the stove for breakfast or your after work stress-reliever workout could power your TV.

Despite the impending comparison to a hamster on a wheel, I say bring it on. I would happily pedal away my PG&E bill.

So, readers, if you could power your home using only energy generated by your own physical strength, would you?

--
Leslie Langan is an emerging technology addict. She is driven by passion for innovation and ideas that improve the world around us.




ReneCardenas

7/23/2012 3:58 PM EDT

All power to the cleaver people of Brazil, make them pay for their crimes to society!

If there was a method to improve on efficiency, it would be great to use at home, but let be realistic. For home use I see no major impact to our large energy footprint. A typical household may use 50 to 100 KWhr per day, so I do not see the human gerbil experiment replacing the city power grid ;-)

Lighting is a practical use, given the improvements of LED efficiency, however they may other practical uses for remote and rural areas.

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EREBUS

7/23/2012 4:11 PM EDT

I think all criminals everywhere should have to work off the expense of their incarceration. If pedaling to generate power is useful to the community, then they should be alloted a power/day routine. Besides, exhausted criminals are much less likely to get into further mischief in prison. Plus who knows, it may turn out to be a great training plan for future Tour de France contestants.

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Frank Eory

7/23/2012 4:20 PM EDT

It seems pretty irresponsible to me. I doubt there is much correlation between a prisoner's strength and motivation to pedal for X hours per day and his readiness to safely re-enter society.

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resistion

7/23/2012 5:57 PM EDT

Parole boards should make the call, there shouldn't be a blind formula.

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SylvieBarak

7/23/2012 6:04 PM EDT

well, yes, obviously. Although, you'd think that if the crime was severe enough, the jail sentence would be too long for peddling anything particularly meaningful off of it! But if it was, oh, I don't know, Tax Fraud or something... then I think it's an awesome way to repay one's debt to society. Not to mention the fact that keeping people in prison is expensive to local taxpayers, so why shouldn't they be put to work?

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resistion

7/23/2012 8:04 PM EDT

Still smacks of buying a reduced prison sentence. Better to let users pedal themselves and let prison sentences be reduced fairly.

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David Ashton

7/23/2012 9:25 PM EDT

You could also use this for Gyms - pedal and generate and get reduced fees.....

Ref some of the comments above - anyone who is willing to pedal for 16 hours to get a day off their sentence must have something going for them. 16 hours is a LOT of pedalling.

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Nvidia

7/24/2012 6:40 AM EDT

I dont think it is mentioned that an inmate has to cycle continuously for 16 hrs; I think they might be logging the total number of hours that an inmate cycles, and then for each block of 16 hrs a day is deducted from the sentence....

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resistion

7/23/2012 10:01 PM EDT

If we think of this as a community service, maybe it could be a sentence in and of itself?

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huddo

7/26/2012 5:45 AM EDT

yep.you got it.
cheers

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eewiz

7/23/2012 10:27 PM EDT

yup 16 hours of pedaling is a lot. Should be more like 8 hours or something.

BTW I really doubt, whether this kinda things will really help to solve the power problem. For pedaling 16 hours a day, the prisoners will have to consume "additional energy" as food. And there are 2x conversion losses in this process. ie food to stored fat, Fat to mechanical energy. Instead the food can be directly converted to energy for better conversion efficiency. Anyway, in this case the prisoners are getting some good exercise atleast :)

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Nvidia

7/24/2012 6:40 AM EDT

I dont think it is mentioned that an inmate has to cycle continuously for 16 hrs; I think they might be logging the total number of hours that an inmate cycles, and then for each block of 16 hrs a day is deducted from the sentence.... Same comment for David Ashton above

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Juho L

7/24/2012 1:06 AM EDT

This kind of idea could be used in gyms, as mentioned above. Of course the resulting energy would be minimal to the total energy consumption of the gym facility, but every kWh saved is good thing. After all, cutting down the energy consumption is all about making small decisions and innovations that together result in big savings.

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eewiz

7/26/2012 1:52 AM EDT

Many gyms are already using it.
http://www.time.com/time/business/article/0,8599,2032281,00.html

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chrisnfolsom

7/24/2012 4:30 AM EDT

Interesting idea although transporting the batteries will probably use more energy than was created by the bikes..... Hook it to the grid - small inverters are being used by rooftop solar cells now... Still though the 200w is not much, but perhaps to keep the TV on at home? BTW I think anything an inmate does above and beyond existing is great - especially if the activity helps them to pay back society, or at a minimum support themselves.

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nicolas.mokhoff

7/24/2012 7:14 AM EDT

The liability of a rider having a heart attack on a bike needs to be considered before applying the exercise for watts formula across the penal system. Better they apply themselves to fixing potholes in big cities. Those convicts already have a song to keep the beat: http://www.oldielyrics.com/lyrics/sam_cooke/chain_gang.html

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SylvieBarak

7/24/2012 2:44 PM EDT

Yeah, but bending to fill in a pothole... they could put their back out ;) I don't see why they don't just power the prison itself using the energy, instead of transporting the batteries into town. Prisoners want a TV? Pedal for it. They want warm food? pedal for it. That seems fair to me. pedal for perks.

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Davetech

7/25/2012 8:37 AM EDT

...so, what I'm wondering is: is that day that the sentence is reduced by included in the 16 hours that they were peddling? Net 1 day or gross 1 day?

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huddo

7/26/2012 5:50 AM EDT

assuming one day is 24 consecutive hours.!?

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huddo

7/26/2012 5:52 AM EDT

damn good question. we must consider whether we are allowed to make profit with our slaves.
cheers

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KB3001

7/25/2012 9:10 AM EDT

I have always thought prisoners should pay for the tax-payer expense of holding them in secure and habitable places. I actually think they should do a 9 to 5 job (whatever society needs) in exchange for their full-board. I am not sure their sentences should be reduced as a result though...

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huddo

7/26/2012 5:56 AM EDT

fully agree with your line of thinking.
naughty people will be tolerated if they enrich(aka improve the lives of people around them).otherwise...it's the whip!
i say yes.

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dylan.mcgrath

7/25/2012 12:18 PM EDT

Many of the responses to this post are centered on the question of whether it's right or wrong that prisoners can reduce their sentences by pedaling to power street lights. I agree that this is kind of a dicey proposition, particularly in the case of violent offenders. (But like Sylvie, I would hope that those offenders that have been convicted of violent crimes would not be eligible.)

But as to the other question that the author poses, what if you could use your own pedal power to heat the stove for breakfast or to power your TV, I'm all for it. While I agree with the earlier comment that this probably doesn't have the potential to replace that much of the power we use, every bit helps, and if we could harness the energy we expend in our daily workout, anyway, to help offset the energy we use, why not? If the efficiency can be improved, all the better.

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Frank Eory

7/25/2012 4:58 PM EDT

I agree with you on that point. Many of us go to the gym regularly and burn some of our stored energy making weights go up and down or on a cardio machine, and usually we're listening to music and/or watching the big screen TVs while we're doing it.

At the very least, the energy we willingly expend for fitness could be used to help power those TVs, or the lights at the gym, or to charge our portable music players or phones.

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huddo

7/26/2012 6:44 AM EDT

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.

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Nando Basile

7/26/2012 10:22 AM EDT

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.

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mVanPelt

7/27/2012 6:28 PM EDT

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.

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ChrisJ555

7/26/2012 1:21 PM EDT

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!

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TFCSD

7/27/2012 1:54 AM EDT

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-

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TFCSD

7/27/2012 1:55 AM EDT

-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.

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agk

7/27/2012 8:39 AM EDT

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.

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seaEE

7/27/2012 10:45 PM EDT

I like the idea of prisoners doing some work that benefits society, but somehow I doubt that anyone's electricty bill will drop because of this program.

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WKetel

8/2/2012 6:06 PM EDT

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?

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