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Some hard numbers for block heater operation.

Discussion in 'Gen 2 Prius Main Forum' started by Frank Hudon, Sep 15, 2006.

  1. Frank Hudon

    Frank Hudon Senior Member

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    This summer I bought a WattsUp Pro and have my block heater timer plugged into it giving the following readings.
    Watts average about 380
    cost per kw 0.0619 cents per
    block heater timer set to turn on at 2:00 AM and off at 6:37 AM 4 days a week
    cost per 4 day week, 43.2 cents
    cost per month of 4 day weeks, $1.73
    benifit summer, 4 blocks to get into S4 Nomal 12 blocks
    benifit winter, 9-12 blocks to get to S4 Normal 1.7 Kms (21blocks) with winter lips installed
    ICE at start up, 52-54C (125-129F) Summer
    ICE at start up, 38-42C (100-107F) Winter

    this is on a 2k3 Prius without the thermos, others with the 2k4-6 will probably not get the net benifit that I do but at least here is some numbers that might come in handy for those considering a block heater and some of the costs involved in it's operation.
     
    #1 Frank Hudon, Sep 15, 2006
  2. sl7vk

    sl7vk Member

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    <div class='quotetop'>QUOTE(Frank Hudon @ Sep 15 2006, 11:11 PM) [snapback]320385[/snapback]</div>
    Frank, I've had more then just a couple of beers tonight.... I guess from your post that you're an advocate of the block heater. How much si the model that you bought and where did you get it? My car is housed in a garage, but the mornings are about 30 degrees F here in the winter. Thanks!
     
    #2 sl7vk, Sep 15, 2006
  3. Rangerdavid

    Rangerdavid Senior Member

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    I'd be interested also, but our winer mornings here are frequently single digits F. How much was it, and what's involved in the install?
     
    #3 Rangerdavid, Sep 15, 2006
  4. Frank Hudon

    Frank Hudon Senior Member

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    the block heater that I have is a Toyota OEM heater installed before I bought the car. If you do a search here on PC for block heater you'll find at least a half dozen threads with at least 500 posts on them. If your garage is only at 32F in the morning you'll get a benifit from a block heater. More than just better gas mileage, a heater that actually gets the car warm and reduced emissions as well. Not sure what the ICE temps are on the G2 with the thermos on start up with a block heater but has to be better than I get. My winter time MPG is on the order of about 2-3 mpg better with the block heater and our fuel cost's about $4 US gallon. Winter lips on mine or a full front like hdrygas has on his 2k4 helps keep the temp up in stop and go traffic. Several others have blocked off the grill/rad to help keep the ICE temps up so the car will go into S4 in traffic in winter time.
     
    #4 Frank Hudon, Sep 15, 2006
  5. bee13

    bee13 Member

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    I installed a block heater in my '05 package 4 in December of this past winter. I set up a timer that started the heater 3 hours before I departed for work. It was my first winter with the Prius so I don't have a non-heater winter to compare with. It must be working; The engine compartment is definately warm to the touch after three hours of pre-heating so it has to be trimming the exhaust system warm-up cycle to some degree and saving some gasoline...
     
    #5 bee13, Sep 15, 2006
  6. Mojo40

    Mojo40 New Member

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    <div class='quotetop'>QUOTE(Frank Hudon @ Sep 15 2006, 08:11 PM) [snapback]320385[/snapback]</div>
    This seems like some good data to show the Return on Investment for a block heater, but it doesn't appear to go all the way. Can you determine the savings (in reduced gas burn) bases on use of the heater? Assuming gas stays around $3/gallon, how long before the block heater + electricity is paid for? Also, consider doing a Carbon Dioxide ROI. In other words, does using the block heater result in more or less CO2 being being generated? I might consider losing a small amount of money (slightly negative ROI) using the block heater if it prevents a lot of CO2. Thanks.
     
    #6 Mojo40, Sep 15, 2006
  7. ScottY

    ScottY New Member

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    <div class='quotetop'>QUOTE(Frank Hudon @ Sep 15 2006, 11:29 PM) [snapback]320399[/snapback]</div>
    I would suggest that you monitor the temperature of the interver and MG's if you are blocking the lower portion of the radiator on the Gen II Prius.

    [​IMG]
     
    #7 ScottY, Sep 15, 2006
  8. Frank Hudon

    Frank Hudon Senior Member

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    <div class='quotetop'>QUOTE(Mojo40 @ Sep 15 2006, 08:35 PM) [snapback]320402[/snapback]</div>
    all our electricity is hydro generated. no coal no nuke, just good old water turning a turbine. 2-3 mpg improvement. gas cost us about $4 a US gallon.

    <div class='quotetop'>QUOTE(ScottY @ Sep 15 2006, 08:43 PM) [snapback]320403[/snapback]</div>
    almost all of us that I know that block off the rads or the grill have scanners or CAN-view's to monitor temps. I have a MiniScanner on my Classic and CAN-view on the wife's G2. The temps on my Classic finally got to the range where I considered the winter lips of no advantage in May of this year, and took them out, I'll put them back in probably the first of October and monitor the temps but by then the daytime OAT will be in a range where blocking the grill won't cause dangerous temps. If they do I'll pull them out. Takes only 30 second to put them in or take them out. In fact with the OAT were currently experiencing I could probably put them in now.
     
    #8 Frank Hudon, Sep 15, 2006
  9. ScottY

    ScottY New Member

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    <div class='quotetop'>QUOTE(Frank Hudon @ Sep 15 2006, 11:59 PM) [snapback]320405[/snapback]</div>
    Ok, cool, good to know!

    I want to point that out so that people won't just block their rad/grill without monitoring the temperatures.
     
    #9 ScottY, Sep 16, 2006
  10. FireEngineer

    FireEngineer Active Member

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    You can purchase the block heater at MetroToyota for $33.00 plus shipping. Classic is part CO140-00885, 04-06 Prius is part CO140-00889. These are Canadian part numbers.

    Difference between the two; 00885 has no metal surround of the terminal area on the heater as the 00889 does, 00885 has a different clip than 00889 but both are the same length, 00885 has a 5 foot cord and 00889 has a 6 foot cord. For a Classic I would get the 00889 just for the end piece of the heater, seems better built and more protective of the cord end.

    Install is fairly easy from under the car as long as you dont' have huge forearms. From the top you would probably have to remove the windshield cowl, easier install but a pain to take on and off.

    Wayne
     
    #10 FireEngineer, Sep 16, 2006
  11. David Beale

    David Beale Senior Member

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    Frank, that's good info., thanks. I used to live where you are, moved here over 30 yrs. ago. For those worried about covering the front of the car, there is a space between the rad and the front. The fan can draw air from this space, and it tends to negate any problems with rad overheating. At least in my experience with other cars/trucks.

    The biggest thing covering up the front does is give the fan complete control of air flow. Moving doesn't cause air flow, only the fan does. As long as the system (fan) isn't stressed (underdesigned) there will not be a problem. I doubt a 1500cc high efficiency engine is going to stress it. ;)

    So the Toyota "block heater" is an external type? Not put in through a frost plug? I might think about using a "recirculating heater" instead. They go into the heater circuit, and use a solonoid to pump coolant through. It heats the whole engine and the interior heater core (when the heater valve is open). We consider them the ultimate solution here in "real winter" country. ;)

    One other thing I've been wondering about - is it reasonable to insulate the engine block? I was thinking of aluminum foil backed rock wool - perhaps 1/2" to 1" thick. Just wondering how accessable the block surface would be for installation of this kind of stuff.
     
    #11 David Beale, Sep 16, 2006
  12. Frank Hudon

    Frank Hudon Senior Member

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    Dave the block heater that Toyota supplies is inserted into the ICE block and heats the coolant thru convection instead of conduction, like a normal block heater (frost plug insertion type) and is as far as I'm concerened better than a recirculating pump type. This one just gets lubed and pushed into a pre machined cavity on the block. I'm on my second year with it and use it now winter and summer and get better gas milage as the real benifit. As you know our winters are nothing like Edmonton or Dawson Creek where I lived for 12 years and blocking off the grill and being able to monitor the ICE temps and MG's and Inverter as well, I've never seen the temps get out of hand. In late April I managed to get the ICE temp to 100C only once on Boundary Road hill under full throttle the whole way and 1 block past the top it was at 92C and the thermostat opens at 87C and the fans come on at 100C so the fans were controlling it very well. OAT if I remember correctly was in the low 20's. Up your way when the temps get into the single digits I'd close it up till spring. As for insulating the ICE block I really think it'd be a waste of time. But experiment to your hearts content! just post your results.
     
    #12 Frank Hudon, Sep 16, 2006
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