How do you convert Heat into stored Energy/Electricity?

  • Context: High School 
  • Thread starter Thread starter nukeman
  • Start date Start date
  • Tags Tags
    Convert Heat
Click For Summary

Discussion Overview

The discussion revolves around the conversion of heat energy into stored energy or electricity, specifically exploring methods to harness heat from a stove top and store it for later use. Participants consider various theoretical and practical approaches to this concept.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant questions how to harness heat from a stove top and store it in a battery or similar device.
  • Another suggests that converting heat into mechanical motion, such as using a turbine, is necessary to generate electricity from heat.
  • A different participant proposes heating water and storing it in insulated containers as a method of energy storage.
  • There is a discussion about the potential energy generation from a turbine connected to a bathtub nozzle, with estimates of around 100W being mentioned.
  • Some participants express uncertainty about the feasibility of generating 100W, suggesting that 50W might be more realistic.
  • One participant introduces the concept of a Stirling engine, noting its low efficiency in converting heat to electricity.
  • Another participant mentions magnetohydrodynamic (MHD) generators as a method to convert heat into electricity, describing the underlying principles without asserting its practicality for the original question.
  • There is a reference to a new alloy that can convert heat directly into electricity, although its relevance to the discussion is not fully explored.

Areas of Agreement / Disagreement

Participants express a range of views on the methods of converting heat to electricity, with no consensus reached on the most effective approach. Some ideas are challenged or refined, but the discussion remains unresolved regarding the best method to harness heat energy.

Contextual Notes

Participants mention various assumptions, such as the efficiency of different methods and the cost of electricity, but these aspects remain unresolved and depend on specific conditions.

nukeman
Messages
651
Reaction score
0
Hi everyone,

I am no expert in any means, so if what I am asking is silly, just tell me.

This is an example.

Lets say I have a stove top, and I turn it on full for an hour. Without putting anything on it, how can I harness the heat energy and store it, into let's say something like a battery, or anything I can use to power something.

The stove top is giving out some great heat for an hour. I am wondering if there is a way to harsness the heat energy the stove top is giving off, and storing it.

Does this make any sense?
 
Physics news on Phys.org
Normally you'd need to convert that heat into mechanical motion which can convert that into electrical energy.

Like how a turbine is used to generate electricity. Other than that, I do not think there is any directly way to go from heat -> electricity.
 
nukeman said:
Hi everyone,

I am no expert in any means, so if what I am asking is silly, just tell me.

This is an example.

Lets say I have a stove top, and I turn it on full for an hour. Without putting anything on it, how can I harness the heat energy and store it, into let's say something like a battery, or anything I can use to power something.

The stove top is giving out some great heat for an hour. I am wondering if there is a way to harsness the heat energy the stove top is giving off, and storing it.

Does this make any sense?
You could heat water and put the water in insulated thermos bottles. Depending on what you want to use the energy for later on, you might want to choose different methods of storing it.
 
Thanks for the reply!

I see what you are saying, thanks for clearing that up.

If you can answer this: Example, if I was to hook something up to my bathtub nozzle, that when I fill up the bathtube and as the water pours out of the nozzle it spins a super tiny turbine, how much energy could it store, if theoretically I had something to store the power.

?




rock.freak667 said:
Normally you'd need to convert that heat into mechanical motion which can convert that into electrical energy.

Like how a turbine is used to generate electricity. Other than that, I do not think there is any directly way to go from heat -> electricity.
 
russ_watters said:
You might generate 100W or so.

Thanks for the reply!

Forgive me, but generally what could that generate and for what time period?

:)
 
I'm not sure what you mean - 100W is 100W.

...though the time to fill your tub is probably 5-10 min, right?
 
russ_watters said:
I'm not sure what you mean - 100W is 100W.

...though the time to fill your tub is probably 5-10 min, right?

I see. So, if I am getting this right, if it takes me 10 minutes to fill my tube, and generates 100W, I could run a 100W light for 10 minutes?
 
  • #10
Hey really appreciate the info here!

Would you happen to know where I can get info on how much powering a 100w light costs for 10 minutes, or whatever timeframe to go by?

BTW: Awesome astrophotography page! I just bought my first telescope, 6inch dob skywatcher. After I get much better using it, I want to eventually go to something simular to your setup. Nice pics!



russ_watters said:
Correct.

...also, I just ran some quick numbers and 100W might be a little ambitious. 50W is more realistic. Here's a calculator for pump (or turbine) power: http://www.engineeringtoolbox.com/pumps-power-d_505.html
 
  • #11
I couldn't help but be reminded of http://www.smbc-comics.com/index.php?db=comics&id=2045#comic".

To make this post on topic and useful, a watt is a unit of power. Energy is often confusingly measured in kilowatt hours, i.e., the energy used by a 1 kilowatt device over 1 hour. To get energy usage just multiply power by time. A 100 watt bulb ran for 10 hours is 1000 watt hours (1 kilowatt). The price of a kilowatt hour varies, and you can check your electric bill for a local price. A general estimate for the US might be 15 cents per killowatt hour.
 
Last edited by a moderator:
  • #12
nukeman said:
Would you happen to know where I can get info on how much powering a 100w light costs for 10 minutes, or whatever timeframe to go by?
Any electric bill will do. My electricity costs about $.16/kWh so 100W for 10 minutes costs about $.0027
BTW: Awesome astrophotography page! I just bought my first telescope, 6inch dob skywatcher. After I get much better using it, I want to eventually go to something simular to your setup. Nice pics!
Thanks!
 
  • #13
Hi, nukeman
Wiki radioisotope thermoelectric generator may be of your interest. Also heat sources of high and of low temperatures produce electricity by technology applied in coal or oil fire or nuclear power plants.
Regards.
 
  • #14
You can turn a temperature differential directly into electricity using a http://en.wikipedia.org/wiki/Stirling_engine" . The efficiency is fairly low however, and suffice it to say, you spend a lot more energy running the stove then you could get back from the heat.
 
Last edited by a moderator:
  • #15
I want to point out that magnetohydrodynamic (MHD) generator wasn't mentioned. Such system involves a container with ionized gas (plasma), a pipe in with a horizontal constant magnetic field turned on and electrodes at the top and bottom sides of the pipe. If one used the heat to raise kinetic energy of gas inside the container, then releasing gas through the pipe and the magnetic field would make the positive ions and negative electrons flow vertically into opposite directions due to Lorentz force, thus giving a potential difference between the electrodes.
This design is only one type of MHD generators (Faraday's, to be exact). Wikipedia gives other two: Disk and Hall generators.
I don't think that my answer is useful for nukeman, but such ways of getting electricity by only having a heat source should also be kept in mind :)
 
  • #17
russ_watters said:
Any electric bill will do. My electricity costs about $.16/kWh so 100W for 10 minutes costs about $.0027 Thanks!

The OP also ought to check to see how much he pays for the water. It's bound to be more than the value of the electricity he generated.
 

Similar threads

High School To confirm if I am correct about the role of voltage in a circuit
  • · Replies 13 ·
Replies
13
Views
2K
High School Where Do Electrons Go When a Battery Loses Charge?
  • · Replies 22 ·
Replies
22
Views
8K
High School Why does hot water rise to the top of a water heater?
  • · Replies 66 ·
3
Replies
66
Views
5K
High School Distribution of energy in the electric field surrounding an electron
  • · Replies 2 ·
Replies
2
Views
1K
High School Some Questions about Electric Current/Capacitors to help my understanding
  • · Replies 7 ·
Replies
7
Views
2K
Undergrad Mechanism of Energy Conservation in Zero-Amplitude Sum of EM Waveforms
  • · Replies 21 ·
Replies
21
Views
3K
High School Can a Heat Pump and Stirling Engine Create a Perpetual Energy Cycle?
  • · Replies 6 ·
Replies
6
Views
4K
High School How is energy stored in these fields?
  • · Replies 2 ·
Replies
2
Views
1K
High School Can lasers really cause explosions? Let's use a silly hypothetical to find out!
  • · Replies 12 ·
Replies
12
Views
3K
Undergrad Energy Flow From Battery to the Light Bulb
  • · Replies 16 ·
Replies
16
Views
5K