Measuring electrical useage

Discussion in 'Electrical Forum discussion & Blog' started by Rysis, Mar 5, 2012.

  1. Rysis

    Rysis New Member

    Messages:
    5
    Location:
    PA
    Hello,

    I was wondering if there was a device or gadget available that I could wire in before my hot water heater to see how much power it is drawing. My reasoning for this is that I have seen some simple hot water reclaiming ideas that would work with my wood stove. Is it really worth the effort and cost to reclaim that heat to the water heater to save on electricity?

    Thanks!
  2. jwelectric

    jwelectric Electrical Contractor/Instructor

    Messages:
    2,531
    Location:
    North Carolina
    Not wanting to sound like a butt hole but I don’t see any reason to have an appliance to heat hot water. If the water is already hot why would one want to heat it even more?

    It is a water heater or if an adjective is used to describe the appliance it would be a cold water heater. The appliance heats cold water not hot water.

    Now just what does the entire above have to do with the question? Nothing, I was just bored and wanted to practice my typing skills.

    There are several devices on the market today that can be used to measure the kilowatt per hour usage of just about any appliance. They can be programed to the amount you are charged per KWH and show just what that appliance cost a month. It takes about a week of use to get an accurate amount of cost.

    I have a friend that several years back installed a coil on their wood stove to preheat the water before it entered the water heater. The installation cost around a thousand dollars and it was inspected to ensure its safety. According to him the utility bill did not reflect any difference for a period of one year and if anything the bill was slightly higher.

    In order for this type of installation to work there will need to be a circulating pump installed as well as all sorts of relief valves to keep the water from getting above the 125 degrees or the scald point of the human body. The amount of power usage saved on the water heater will be offset by the pump or pumps depending on the type of system installed.

    In my personal opinion you would be better served by insulating the water heater and maybe installing a time clock to control its usage.
  3. Hackney plumbing

    Hackney plumbing Homeowner

    Messages:
    1,174
    Location:
    Alabama
    To make the water hotter. Thats an easy one.
  4. Terry

    Terry Administrator Staff Member

    Messages:
    14,893
    Location:
    Bothell, Washington
    That was my first thought.
    Heating a section of pipe leading into a water heater doesn't do anything unless it is circulated. Using a pump to do that is adding to the electrical cost.
  5. Rysis

    Rysis New Member

    Messages:
    5
    Location:
    PA
    Thanks Terry, I see a lot of stuff like this out there but when you add the setup costs involved it sometimes doesn't seem worth all the effort. Also, that creates another system that needs to be maintained. Thanks again for your response. :D
  6. Hackney plumbing

    Hackney plumbing Homeowner

    Messages:
    1,174
    Location:
    Alabama
    You dont need a circulating pump if you install the system to work without a pump. Hot water rises and cooler water falls. Thermosiphon.
  7. Rysis

    Rysis New Member

    Messages:
    5
    Location:
    PA
    JW, the idea is that you can use another heat source like a wood stove to maintain the temperature of the water heater. Thus the water heater runs less often and requires less energy. Everyone is pushing the issue about going green but in many cases I don’t find it to be a viable solution, at least not yet.
  8. Terry

    Terry Administrator Staff Member

    Messages:
    14,893
    Location:
    Bothell, Washington
    I could see that happening, installed in a loop. Are you thinking that the wood stove input would be at the lower part of the tank, maybe lifting the tank higher then the wood stove?
  9. Hackney plumbing

    Hackney plumbing Homeowner

    Messages:
    1,174
    Location:
    Alabama
    Yes the tank would have to be higher than the stove and preferably not more than 10' from side to side. Basically you want the tank directly above the stove for the best results.

    This type stuff interests me,I love the discussion. I do not have any experience with these set ups and do not want anyone to mistake and think I'm pulling from personal experiences.
  10. Terry

    Terry Administrator Staff Member

    Messages:
    14,893
    Location:
    Bothell, Washington
    I'm a little worried about pipes passing through a fire box and getting too hot. I haven't seen this done either.

    I did have a customer years ago in Carnation out near the foothills that had a wood burning furnace for his home, and Lama's in the pasture.
    I can't remember what I did for the water heating.
  11. Chad Schloss

    Chad Schloss Member

    Messages:
    329
    Location:
    USA
    This was in a sauna in the Upper Peninsula of Michigan where we stayed a few years back. it was a loop system. Fire box in front to heat the loop, old keg with the top cut off. fill with cold water, cold water flows thru loop and comes out hot. Same type of system i would think. Was able to dip hot water out of keg and soak your feet or add some cold water and bathe with it.

    Attached Files:

    Last edited: Mar 5, 2012
  12. jwelectric

    jwelectric Electrical Contractor/Instructor

    Messages:
    2,531
    Location:
    North Carolina
    What we must keep in mind here is the temperature of the water that will be used by people. It is not as simple as heating water with fossil fuel such as wood and letting this heated water somehow flow through the water heater for potable use.

    The one set up that I am familiar with had circulating pumps that pushed non-potable water through coils in the water heater not the potable water in the water heater through the remote heating device.

    If one was looking at any type of external heat to support their potable water supply I would suggest solar water heater. This is the only Green setup I am aware of. Using fossil fuel for hot water is not Green Technology but the direct opposite. Green Technology is to get away from fossil fuel such as burning wood. The carbon foot print left by burning wood is far from the same carbon foot print used to produce the electrical energy for the water heater.

    Here is a link to one type of solar water heater
    http://www.rheem.com/products/solar_water_heating/
    There are several thousand different units that one could choose from and without a doubt the expense will be less than using a wood stove setup after the tax deductions one can benefit from.
  13. Hackney plumbing

    Hackney plumbing Homeowner

    Messages:
    1,174
    Location:
    Alabama
    Alot of people who are "green" use both solar and a wood fired stove or boiler. The problem with solar is the sun is not always enough to supply the demand for various reasons.

    Tempering valves can be installed control water temp to the fixtures.
  14. jwelectric

    jwelectric Electrical Contractor/Instructor

    Messages:
    2,531
    Location:
    North Carolina
    I am sorry my friend but those items in red above is not Green Tech.

    Green Tech means that there is no fossil fuel being used.

    My wall paper in Green Technology came from NC State University.
    Green Technology is partly about the carbon foot print released into the atmosphere. Fossil fuel such as burning wood leaves a very large carbon foot print therefore it is not Green Technology.
  15. Hackney plumbing

    Hackney plumbing Homeowner

    Messages:
    1,174
    Location:
    Alabama
    You can only be so "green" my friend when you live off grid in the woods.
  16. DonL

    DonL Out of the Trades

    Messages:
    3,921
    Location:
    Houston, TX

    When did wood become a fossil fuel ?
  17. Terry

    Terry Administrator Staff Member

    Messages:
    14,893
    Location:
    Bothell, Washington
    Because only old fossils still use wood?
  18. jwelectric

    jwelectric Electrical Contractor/Instructor

    Messages:
    2,531
    Location:
    North Carolina
    You are right about wood not being a fossil fuel but although this is a little long you can see that wood burning is placed in the same category as fossil fuel when it comes to our planet. Also bear in mind that as we cut trees to burn it takes several years for a seedling to be able to replace or diminish the carbon that the burnt tree made.

    By Beth Daley
    GLOBE STAFF
    Burning wood to generate electricity can be worse for global warming than burning coal, according to a Massachusetts-sponsored study released yesterday. That surprising conclusion immediately prompted state officials to reconsider substantial financial incentives provided to wood-burning plants.
    The six-month study by the Manomet Center for Conservation Sciences in Plymouth comes amid controversy over the proposed construction of two large wood-burning power plants in Western Massachusetts.
    “These findings have broad implications for clean energy and the environment in Massachusetts and beyond," said Ian Bowles, state secretary of Energy and Environmental Affairs.
    Wood-burning has been promoted as a “green” energy source because growing forests can absorb the same amount of greenhouse gases that are emitted from burning wood, essentially canceling out the pollutants.
    But the Manomet study shows that wood burning releases more heat-trapping carbon dioxide into the atmosphere per unit of energy than oil, coal, or natural gas.
    What's more, that increase in greenhouse gases can take a far longer time for forests to absorb than previously thought -- a generation or more in many cases. If a wood-burning power plant replaces a coal-fired one, it can take about 20 years before any net benefits are realized. It can take more than 90 years if a wood-burning plant replaces a natural gas plant.
    The study has important implications for policy as President Obama aims to lower US greenhouse gas emissions some 80 percent by 2050 to avoid the most serious consequences of manmade climate change. Wood is projected to be one of the fastest growing sources of renewable energy in the next decade, but if the benefits take too long to appear, policy makers under urgent deadlines may choose not to embrace it.
    Advocates of wood-burning said that they had not had time to read the full study but that burning wood is renewable and has been viewed as such for years.
    “This industry, which has been around for 30 years, takes forest byproducts and combusts them in a way that is carbon neutral," said Bob Cleaves, president of the Biomass Power Association, a national industry group based in Maine.
    Matt Wolfe of Madera Energy Inc., which is proposing a wood-burning power plant in Greenfield, said the study incorrectly assumes whole trees would be cut to fuel the power plants. Rather, he said, most wood for his plant would come from tree tops and branches left over from logging operations or from storm damage, land clearing for new development, or tree-trimming operations.
    “The study is not representative on how we plan to operate,’’ he said.
    The Manomet Center analysis, however, concludes that there is only a small amount of such leftover wood, and that whole trees will have to be taken to fuel Massachusetts wood-burning power plants.
    The study indicates wood-burning still may make sense in certain cases. For example, heating buildings with wood is more efficient than wood-burning power plants, and it can start helping the environment by reducing greenhouse gas emissions in as little as five years.
    Wood-burning’s environmental benefits can vary significantly, depending on the type of wood or piece of tree being burned, what kind of fossil fuel it is replacing, what type of energy it is producing, and how people manage forests, according to Tom Walker, the study team leader. Many, but not all, types of wood-burning create a “carbon debt” that growing forests gradually repay by reabsorbing gases before a “carbon dividend” begins.
    Massachusetts has offered financial incentives for wood-burning power plants since 2002, considering them to be part of a portfolio of renewable power along with wind and solar. By 2020, state electricity suppliers will be required to get 15 percent of their energy from such green sources. Without the credits, wood-burning is not competitive with more traditional forms of energy.
    But when two large wood-burning (also called biomass) plants were proposed a few year later, in Russell and the one in Greenfield, a large and vocal group of residents opposed them, claiming they would be fueled by cutting trees on public and private lands across Massachusetts.
    The controversy reached a crescendo last year, and in December, the state Department of Energy Resources suspended incentives for new wood-burning plants until the Manomet study could be completed. Now that it is, Bowles said his agency will publicly review the study this summer, and develop new rulesin the fall. The suspension of credits for new plants will continue until then.
    The study counters earlier estimates showing there is plenty of wood available for wood-burning power plants in the state, saying there would not be enough sustainably harvested wood to fuel even one large wood-burning plant. Walker said the study tried to look at what was “economically and socially available” from the forests, meaning in part what landowners would realistically sell.
    Jana S. Chicoine, who has led the fight against the Russell plant, said she was pleased at the findings, calling the study a “policy earthquake. We always made the case this was not a NIMBY issue but a policy failure and now we have the state saying exactly the same thing,” she said.
    John Hagan, president of the Manomet Center, said the report leaves policy-makers with key questions.
    “Do you want to wait 10, 20, 30 years just to get to the point (wood-burning) is as good as coal. That is a real social question: Do we as a society want to make the climate worse before it gets better?”
  19. Hackney plumbing

    Hackney plumbing Homeowner

    Messages:
    1,174
    Location:
    Alabama
    All thats great but the original poster already burns wood. He just wants to get the most out of the wood he is going to be burning.
  20. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,491
    Location:
    Cave Creek, Arizona
    quote; It is a water heater or if an adjective is used to describe the appliance it would be a cold water heater. The appliance heats cold water not hot water.

    You are trying to be "cute", (or channeling George Carlin, because he made that arguement decades ago. He also wondered why we drive on parkways and park in driveways, among other things. ). As soon as the heater comes on, the water is no longer "cold". Therefore it is a "tepid, then warm water heater" but at some point the water WILL be hot, and if the heater is still operating it WILL be a "hot water heater".
    Last edited: Mar 7, 2012
Similar Threads: Measuring electrical
Forum Title Date
Electrical Forum discussion & Blog measuring blower motor current Sep 10, 2013
Electrical Forum discussion & Blog Septic system electrical lines Jun 24, 2014
Electrical Forum discussion & Blog Installing Garbage Disposer electrical Jun 18, 2014
Electrical Forum discussion & Blog One right way to run electrical Jun 5, 2014
Electrical Forum discussion & Blog How to wire outdoor electrical outlet using old hot tub connection? Jun 3, 2014

Share This Page