Science Buddies: "Ask an Expert"

Hi,

I am doing the project, "Decomposing Energy: Extracting Heat Energy from a Compost Pile," and I want to know if I could convert compost heat into usable electricity. I found out the Jean Pain Method and how it uses distilled methane gas to produce electricity. I am wondering if I could apply this to my project and if so how? If there are other ways to produce electricity, I would like to know how to use it in my experiment. I am pretty sure that this project is not an experiment on its own and I need help to make it one.

Thank you

Hi Power of Science,

Welcome to science buddies!

I think you are doing this excellent and challenging experiment that uses actively growing bacteria in a compost pile to produce heat.

https://www.sciencebuddies.org/science- ... ml#summary

And, I understand that you would rather shift the project and work on methane production instead. Here is a project idea on this topic:

https://www.sciencebuddies.org/science- ... deas.shtml

If you have gathered the materials for the first project, then you have everything you need to produce methane. The difference between the heat generating compost pile and a methane producing sample is oxygen. The heated compost pile is aerated frequently to ensure the aerobic bacteria are growing actively. The methane-producing sample is left static and the methane-producing bacteria from the cow manure sample are able to start producing methane as soon as all of the oxygen is gone.

The decision to switch objectives is up to you. If you are almost finished with the heat project, I recommend completing the project as it is. If you are just starting, you could gather bottles and balloons and produce methane instead. If you are too far along to switch, then I recommend saving the methane project for next year.

From personal experience, I can say that anaerobic bacteria (the methane producers) are a little more difficult to grow compared to the aerobic bacteria. And, they grow more slowly.

I hope this helps. Please let us know if you have any other questions.

Donna Hardy

Hi PowerOfScience,

This is a response to your inquiry about the independent and dependent variable from your second post. Please reply to this topic.

You have a great question and it's good that you stopped to ask before proceeding with your project. Please review the following information on variables from this website:

https://www.sciencebuddies.org/science- ... test.shtml

To apply this to your project, you need to first decide if you are doing the heat or the methane-generating project. Then you need to do background reading to decide how you would improve the heat or methane generation. You might design a different compost container, use a different food supply for the bacteria, or perhaps compare cow, horse, and chicken manure.

Whatever you decide to vary is the independent variable; the result that you measure (heat or volume of methane) is the dependent variable. All other parameters in your experiment are kept the same, as much as possible (controlled). You can only change one thing at a time.

You need to do one carefully controlled experiment for a science project. And, it's best if you have time and enegy to repeat the results.

Please let us know if you have more questions.


Donna Hardy

Pushing away the whole fact about methane production that I stated above, are there any others idea that I could infuse with my project to make it have a easy understandable and precise independent and dependent variable? I know that in my project I am trying "to investigate whether the heat from a compost bin or pile can be used to efficiently and effectively heat water." I just realized after spending almost $200 on this project, that is not an experiment. Anything put in a closely compacted space produces heat. Why compost. Why is compost beneficial to my project. The judge at my science fair will probably as me something like: "Why do we need heat energy from compost when I could just heat water on a stove." I cannot answer something like: "Oh, I do not know sir, it was just an abstract idea…trial and error right." Obviously this is an exaggeration of what might happen in the future if nothing changes, and I would not say that, but I would definitely be speechless. I know that I should have asked myself these questions before, but it never occurred to me that I would need to find my own variables and do my own things. I mean I knew that I had to put in some effort and change some of the project, but in this project I literally have to change the course of this whole thing and I COULD NOT POSSIBLY DO IT ALONE. The amount of expansion that I have to put into this project is close to impossible for me. My vacation ends today, and I will have barely any time at all to think how to change this project and I have no ideas at all. I need to make this project produce electricity or anything that makes it something novel... the way I am going with this project I will probably not even make it to my school science fair. This time, I really need some hardcore advice on how to go about my project. Maybe some new ideas could help. I have been brainstorming about how to do something with compost. This is probably the priciest project yet it just runs on basic facts and is put in the advanced section. If the project is put in the advanced section then it should most likely have an awesome idea or at least the basic independent variable, dependent variable, constant, and control. I am sure that depending on the reply given to this, it might greatly help people who might want to do this in the future. I believe that I am speaking for every person that is doing this project or may be doing this project in the future. Please heed my requests.

Thank You,
Your ever faithful ScienceBuddy

Hi PowerOf Science,

It sounds like you have done a lot of work already and have the basis for a viable science project.

Since you just set up one compost bin, you will need to do the experiment on successive days. Your independent variable could be the amount of aeration that you are using (measured in number of times that you turn over the compost).; the dependent variable would be the temperature of the water converted to joules. Or perhaps you can improvise a way to deliver oxygen to the microbes in the compost. Can you think of any other condition that you could easily vary? If so, then that's your independent variable.

The science fair judges will ask you about the significance of your project, and you will explain that you are investigating how to capture energy from a source that is normally wasted. This is a very worthwhile goal. Before the fair, do some more background reading so you will be an expert on this topic.

Does this help?

Donna

Hi Powerof Science,

Here is a website that lists several applications of captured heat from compost piles. You can use this source for inspiration when answering the science fair judges' inquiry about the practical application of your project. The judges will be interested to know that compost heat can be used to heat barns and for other farm applications.

http://smallfarms.cornell.edu/2012/10/01/compost-power/

For your experiment, just devise an alternate way to aerate the compost pile. Measure the results, preferably two times (for both the control and test method) and you'll have a great project.


Donna

Hi Power of Science,

This is a response to your Major Problem 2:

"I need to make at least 3 graphs or tables(preferably not all of graphs or not al of tables). I already tried Excel and I cannot make the data into a graph or table. I need a step-by-step procedure on how to do this, for example:

Table could be something like:
1. In Excel, put "…" for the title, under that put "…" for the first subtitle and "…" for the second
Graph could be something like:
1. In Excel go to charts and pick line

P.S I need actual answers. If you can answer the first and/or second one it does not matter as long as the answer is something that could actually help me and probably others who may do this

Thanks,
Your loyal ScienceBuddy"

Here is my response:

What data have you collected? If your teacher is requiring at least 3 graphs, then you can measure the temperature of water over time, maybe once an hour during the day. This will give you data that you can graph; with time on the x axis; temperature on the y axis. Your second graph can be time on the x axis and joules on the y axis. Perhaps your third chart could be total joules for the control and experimental aeration methods (or whatever your experiment is).

https://www.sciencebuddies.org/science- ... l#overview

If you need more specific answers, then please tell us exactly what you have done so far and what your data you have collected. If the suggestions will not work for you for some reason, please explain why and we'll try to think of an alternative. If you still don't know what to do, please ask more questions. Please confirm what your independent variable is.

Please go through your teacher's instructions for the science project again and make sure you have included every required item, otherwise you will lose points for each omission.

I know it's challenging when you have to change course at the last minute, but this does have the potential to be a great project and I think you have a good start.

Donna

I figured to use living organisms (earthworms) as a treatment to the compost to see whether if it could increase the heat of the compost and am thinking of some other things too.

What email do I need to send some of my data to?

Your's truly,
A ScienceBuddy

Using earthworms is an innovative idea. I'm very interested in seeing your data.

You should be able to attach your results as a .pdf or Excel file to a reply message. When you reply, click on the attachments tab at the bottom of the message and then on the add files button. Search for your file on your computer and then attach it.

Donna

Hi,

I really do not want to send my data online because it will be viewable by other people and I prefer that no one should copy it. I can easily send it from g-mail though if Science buddies has an e-mail account. If there is an e-mail account I would like to know.

A ScienceBuddy

P.S
For moishymull:

Welcome to Science Buddies! Once you click the Ask An Expert tab, you will be directed to the Ask An Expert page. From there, click the New to AAE tab. Choose the Grade level you are in, and the subject that you want the project to be in. Whatever subject you choose, you will be directed to the the topics page where you will see trending topics where you could answer questions that people have. In order to start a new conversation so that you can ask a question click the New Topic button with the asterisk (*). There you can type in the subject and ask the question that you have.

A fellow ScienceBuddy

Hi Power o Science,

I understand your concern about your data. I will be at my computer for the next several hours. If you can post your data; I'll look for the notification of your message and then let you know so you can delete your data. Your data will not be available for everyone to see and will be posted for only a short time. .

If that won't work for you, I'll ask a moderator for assistance.

Thanks for your excellent reply to moishymull.

Donna

Donna's suggestion that you temporarily post the data is a good one. If you are not comfortable doing that, you can email it to me at Science Buddies - [email protected]

I can then forward it to Donna for review. Her responses to you, however, would be here in the forums. We do not put students in direct contact with Experts, and we do not set up email-based mentoring.

Amy
Science Buddies

I won my science fair a couple of day ago! Thanks