diversion loads

what are things that can be used as diversion loads
sean

Comments

  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: diversion loads

    anything that can take the full power that needs diverted. i know that's pretty broad, but accurate. most try to make the diverted power work for them. the most common example would be to power a water heating element to either heat or preheat their water.
  • arcandspark
    arcandspark Solar Expert Posts: 63 ✭✭✭✭
    Re: diversion loads

    I am experimenting using Peltier Thermo Devices as a diversion load. They can be used to generate heat or cold. One side gives around 140 degrees of heat and the other side gets almost to 32 degrees. They are on Ebay real cheap. They usually take 12 volts at 20 amps so putting a few together they can be set up to handle almost any kind of load. I am planning to use them to help heat the battery inverter shed in the winter and cool it in the summer. Results are not completed yet, this project is about number 12 on the list of solar and alternative energy projects, Co-genertion is number 1 on the list. I can tell you this from having had to go repair someone elses wind generator system, Diversion loads are very important. This person had installed 12 GNB Absolyte III 1700 amp 2 volt batteries, very expensive, for a 24 volt battery system. They installed a wind generator and connected it to the batteries through a Trace C40 controller. Dont know how it had been set up but no diversion load was installed. The winds had been very high over a period of about one week and I was called in to replace all 12 GNB batteries that had boiled out the gell acid solution from being over charged. They were all cracked and leaking. The wind generator had been destroyed because the tower had also failed and it all came crashing down to the ground but only after it had over charged the batteries. It was a real mess. Lessons learned from others mistakes, dont use a home made tower unless you are a mechanical strucural engineer, and always install a diversion load on your wind generator system. Take a look at Peltier devices, they have lots of potential as diversion loads. Arcandspark
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: diversion loads

    Yikes! Sounds like almost everything that can go wrong did... :oops:

    For diversion loads, Peltier devices are probably OK... But, in terms of actual cooling efficiencies, standard refrigeration equipment may be up to 4x more efficient.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • arcandspark
    arcandspark Solar Expert Posts: 63 ✭✭✭✭
    Re: diversion loads

    Bill, True, AC and refrigeration is much more efficient and in one of my installation I acutually use a small 5000 BTU window AC unit just to keep the battery shed below 85 degrees in the summer in Texas. Without it the inside shed temp can run around 105  to 108 degrees using only fans for cooling. The Trace inverters run a little hot on those days so the AC unit keeps things from going into nuclear melt down. The owner is running two more 5000 BTU window units the same time the one in the battery shed is running. It puts a bit of a strain on the batteries, but they have handled it for the last two years with no problems. I am just looking for ways to help with cooling, the Peltier devices can be installed with water cooled heat sinks on the hot (+140 degree) side which can help heat DHW for the house while the heat sinks on the cool side would be mounted inside the shed with a small fan blowing the cooled (34 degree) air into the shed. The system is using wasted energy anyway, that can not be used by the batteries once they are fully charged, so even though its not as effeicent, why not use it anyway? Just playing around, its just a hobby for me, so I always like to think outside of the box. My major goal is to find ways to reuse wasted energy, from the generator I reuse the heat from the engine coolant (215 degrees), and engine oil temperature (205 to 220 degrees). It passes through a heat exchanger and is collected in a phase change storage container. Filled with Tin/Lead (plumbers solder) The solder stores the heat for days ( around 180 to 200 degrees) which is removed by pumping hydrualic oil throuh a coil and then to the DHW inside the house  where it heats the water to around 120 to 125 degrees. The propane water heater almost never has to turn on. Also how about installing a radiator in the HVAC air duct and running the oil through it to help heat the house during winter time. An auto air conditioning compressor can be installed on the generator engine, and can supply up to 18,000 BTU of AC air for the home in the summer time. If you are going to run the generator, why not squeeze every drop of energy out of it you can while it is running. Just a few ideas I am currently working on. I feel Co-generation systems will be incorperated in with alternative energy, in the near future.      Arcandspark
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: diversion loads

    And don't get me wrong--I am all for experimentation and finding "odd ways" to do something new and wonderful. I would drive folks at work nuts just twisting right around roadblocks (both engineering and bureaucratic). :wink:

    I have loved the idea of Peltier Devices--but could never justify using them except in very limited (and with lots of excess power available--like the small cooler for use in cars and hotels) situations.

    Many times, heat pipes seemed to be better solution for a lower power method of moving heat around.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: diversion loads

    i think i'd be a bit leary that the peltiers could fail and that would leave no load again. even water heating elements have opened up creating havoc to the systems. reliability is paramount in the diversion loads. there isn't anything wrong with paralleling another load to backup the original in case one load should fail.
  • Patman3
    Patman3 Solar Expert Posts: 62 ✭✭✭✭
    Re: diversion loads

    Those Peltier coolers ARE really nifty, but being so thin (1/2"?) how to separate the cold side from the warm side seems ineffecient. They can be stacked in series I suppose to get them thicker. How large, or how much surface area do your coolers have? Typically they are only a couple inches square. You mentioned heating water, I would like to see some pictures of how that assembly would work. Immersing the heat sink inside a pipe? I've been toying with a drink holder idea with one of these Peltiers in the bottom to either heat or cool your drink, depending on the polarity. Maybe they exist already? If not I want the patent.
    As a diversion load it sounds better than a heater coil.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: diversion loads

    patman,
    peltiers are not normally complete when you get them. if you were to just apply power to them they would blow unless they came with heatsinks preinstalled. they are also designed for certain voltages and can vary to quite a degree up to their voltage design point. i had downloaded some time ago the melcor thermoelectric design/selector guide from melcor's site and if you just play with it you'll see what i mean. the heatsinks are rated in thermal resistivity just as they'd do for transistors or power ics.
  • System2
    System2 Posts: 6,290 admin
    Re: diversion loads

    Just the post I was trolling for.

    We are installing Wind and Solar systems on a boat. Handling the Solar through an Outback MX60 will do just fine, however we are planning to install 2 windmills that have a potential of 1000 watts @ 30 knots (app 35 mph) wind. We need to work out 2 diversion loads, each connected individually to a separate Tristar 60. The problem with coils is that they need so much "open space" around them for cooling (and space is a super luzury on a sailboat!) The idea of peltier caught my fancy, but I need to do more research. Anybody else have good ideas of how we can divert this much power on a ocean going sailboat?

    We run 6 GL16 6v batteries wired in 12v, have 4x Sunpower 90 watt solar panels and 2 custom windmills rated at 480 watts each (can handle up to 600 watts for a short (1 - 2 hour) blow).
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: diversion loads
    DogBonz wrote:
    Anybody else have good ideas of how we can divert this much power on a ocean going sailboat?

    Equalize batteries 1x a month.
    Fresh water maker
    then
    Electric water heater, say a 10 gallon one, that can be stowed in the bilge area, but if you are at anchor, and expect a big blow, lock or park the windmills, or you may have boiling water. Run the microwave, or enjoy a hot shower.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: diversion loads
    DogBonz wrote:
    The idea of peltier caught my fancy,

    Still need the air space for cooling. Peltiers need to dissapate the heat they create (12V @ 8A = 96 watts) PLUS the heat they are pumping, another 20watts. Then, you only get tempeture diferential of about 40F from hot side to cold side, so if you want to cool someting, you have to keep the hot side of the heat sink really cool. I built a Peltier Fridge out of a big ice chest, and used it for a month, when my fridge died. It worked, and I had a big 500W 12V transformer to run it from. It pulled 8 amps at 12V, and has a 10" W x 19" L x 2"H finned heat sink, with muffin fan on it, to keep the hot side cool. Too much hassle to make in a sailboat, unless you want to have a special built fridge. Run 6 months and see what sort of surlplus power you actually have.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • Frank
    Frank Solar Expert Posts: 54 ✭✭✭
    Re: diversion loads

    DogBonz: I agree with Mike re the water heater: just make sure there's a functional T/P safety valve and that it blows off in the bilge. Imagine hot water w/o having to run the engine or generator!
  • System2
    System2 Posts: 6,290 admin
    Re: diversion loads

    Thanks for the input. The problem here is that we have a space limited situation on the sailboat, a monstrous heat sink on a muffin fan doesn't sound like the solution either.

    As well with a potential of almost 1000W output (500 W from each wind generator), and with two Tristar 60 Diversion Load regulators) we need to devise how to split the load. If we went with a water heater on one controller (which has also been tough as we have an Isotemp water heater and every 12V heating element I've found says "...but doesn't fit the Isotemp...". However I have found a cool heating element that has 120VAC and 12VDC elements on it. It uses a standard 1" pipe thread, so might be able to get a custom adapter flange banged together. It can handle up to 600 W (on 12VDC) thus might be an option.

    Here's an idea that needs some suggestions & inputs (from those that have already blown up, burned down and shorted things out trying it :-D)
    For the other Controller Diversion Load, I was thinking of a standard wound coil in a metal box. The box could be lined with heat insulating foam (the same they use on the inside of boat engine rooms). This "cooling box" would have a high volume fan blowing outside air into the box and the outlet on the box would have a "Y" adapter. The "Y" could either be directed to blow the warmed air into the boat; or turned to blow it out through a vent. The cruising up here on the BC/Alaska coast needs all the help it can get for fall/winter/spring heating. Any ideas or suggestions or cautions on this??

    Thanks to all and Happy 2007! :evil:
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: diversion loads
    DogBonz wrote:

    For the other Controller Diversion Load, I was thinking of a standard wound coil in a metal box. The box could be lined with heat insulating foam (the same they use on the inside of boat engine rooms). This "cooling box" would have a high volume fan blowing outside air into the box and the outlet on the box would have a "Y" adapter. The "Y" could either be directed to blow the warmed air into the boat; or turned to blow it out through a vent. The cruising up here on the BC/Alaska coast needs all the help it can get for fall/winter/spring heating. Any ideas or suggestions or cautions on this??
    I don't know the quality of their parts, but try getting a truckers/automotive "instant" window defroster. Runs off 12V about 10 Amps, has fan in it.
    Maybe try makeing a water heater system, use what elements you can, and build tank to fit the element bung. Or even install one thru the hull for boiling the open ocean water.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,