Windmill Dump Load Alternatives - How to set up multiple DIY water heaters?

crystaleye
crystaleye Registered Users Posts: 5
Hello, I will be living high up in the mountains about 1000m and above. The major appliances which I will use in my house besides light bulbs of course are a normal sized fridge, washing machine (once a week at the most), food steamer (twice a day at the most), slow cooker (12 hours a day at the most), kettle ( a few times a day depending on the weather), juicer (twice a day at the most).

If I would to buy 3-4 1kw windmills, a few solar panels and some deep cycle batteries, what can I use as a dump load?

I am considering building a few diy water storage tanks with heaters in them to be dumploads.. say about 3 diy water storage w heating elements.. how do i configure things in such a way that when the water inside the first water storage tank gets too hot, then the electricity will cut off and the heating element for the second water storage tank then gets turned on? So if the water inside the first water storage tank isn't hot enough, the heating element for the second water storage tank will stay shut off?

Thank you for your advice.

Comments

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Windmill Dump Load Alternatives - How to set up multiple DIY water heaters?

    Welcome to the forum.

    My advice would be first of all to get some firm numbers on the loads you want to supply. Most of those things you mention are pretty hefty power consumers. Refrigerator will be around 1kW hour +/- per day. Washing machine may be low on kW hours for the week, but when it is used it will draw a hefty amount of power. Things like the steamer, cooker, and kettle won't be much in Watt hours but will draw quite a few Watts when on as they are all heaters and as such likely to be greater than 1000 Watts. This necessitates sizing the inverter, battery bank, and thus recharging source to handle those loads.

    My second piece of advice would be to forget about wind power. Even though it may seem windy there, you may find it isn't really that much when it comes to producing power. The cost of the turbines can be quite high for the power they produce. Especially when you add in the cost of putting up proper towers so the blades are in "clear air" not turbulence. Solar panels produce more dependably for less $ per Watt.

    You are going to need back-up power no matter what, and that means a fuel-powered generator. Considering the occasional use heavy loads you have, you may want an inverter that will function with gen support allowing the two to work together when load demand is high and shutting back to just the inverter when it isn't.

    At this point there is no sense in talking about dump loads at all as you aren't at that stage in the planning yet.
  • NorthGuy
    NorthGuy Solar Expert Posts: 1,913 ✭✭
    Re: Windmill Dump Load Alternatives - How to set up multiple DIY water heaters?
    crystaleye wrote: »
    If I would to buy 3-4 1kw windmills, a few solar panels and some deep cycle batteries, what can I use as a dump load?

    There are numerous ways to set up stage heating. One of the posters here - Chris Olson - has it running.

    Based on your load description, my wild guess would be that you need between 5 and 10 kWh/day of loads. Solar is much more practical than wind unless you have some very unusual situation. To support your loads, few solar panels will not be enough. You're probably looking at least at 4 kW solar array (if I guessed your loads well).

    If you want to add heating to this, it might be cheaper to use direct solar heating instead of PV, and possibly complement it with PV when you have excess.

    A good place to start, is to list all your loads, measure or estimate their power consumtion, and then sum them up. Also a good idea is to look at distribution over the day - which loads can be done on excess energy (such as washer), which need to run at night (such as fridge).

    Equally important thing is the weather. What is your worst season, how much sun do you get during this bad season, etc.
  • bill von novak
    bill von novak Solar Expert Posts: 891 ✭✭✭✭
    Re: Windmill Dump Load Alternatives - How to set up multiple DIY water heaters?
    crystaleye wrote: »
    If I would to buy 3-4 1kw windmills, a few solar panels and some deep cycle batteries, what can I use as a dump load?

    Anything you like. It must be a reliable load i.e. you can't just use a whole lot of 100 watt light bulbs, since they burn out. If the windmills are DC or wild AC then make sure you get a load that works with that power source, so an inverter failure won't cause windmill self-destruct.
    I am considering building a few diy water storage tanks with heaters in them to be dumploads.. say about 3 diy water storage w heating elements.. how do i configure things in such a way that when the water inside the first water storage tank gets too hot, then the electricity will cut off and the heating element for the second water storage tank then gets turned on? So if the water inside the first water storage tank isn't hot enough, the heating element for the second water storage tank will stay shut off?

    Well first off one really big tank is a lot easier/cheaper/more reliable than several smaller ones.

    Secondly it's easy to set up a relay diversion system such that the load is diverted to the next tank once tank 1 reaches operating temperature. It's basically just a thermostat and high power relay. MAKE SURE that your last load will take power forever i.e. it is just a bunch of power resistors or an element in a tank with no thermostat.
  • crystaleye
    crystaleye Registered Users Posts: 5
    Re: Windmill Dump Load Alternatives - How to set up multiple DIY water heaters?

    I was thinking using solar as primary and windmill as secondary. However due to the unpredictable nature of clouds these few years, it seem a safer option to use windmill as a primary power option and solar as secondary.

    Modern Fridges only draw 300-500 watts of power nowadays don't they? Also I am not sure if any of you are living in the mountains 1000m and above but wind speeds get higher the higher you are up the mountains.

    My last load will be a really high-powered power resistor. If anyone has any plans on how to make a DIY water heater with its own heating elements which shut off if the temperature is too high, that would be very help. Thermostat and high power relay sounds good and i wanna see how to properly configure such DIY water heaters.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Windmill Dump Load Alternatives - How to set up multiple DIY water heaters?
    crystaleye wrote: »
    I was thinking using solar as primary and windmill as secondary. However due to the unpredictable nature of clouds these few years, it seem a safer option to use windmill as a primary power option and solar as secondary.

    You need to know the climate for your area regarding whether you actually get enough wind to make it worthwhile. You would be looking at towers 50' high or more to catch winds sustaining around 20 MPH. Usually, even with clouds, solar is a more sure-fire thing.
    Modern Fridges only draw 300-500 watts of power nowadays don't they?

    Running Watts on a 'frige is usually <200. But they have a pretty healthy start-up surge and can draw 500 Watts during defrost cycle. It all depends on the 'frige in question. The big issue is not how much the draw, but how much they use: the daily Watt hours. It is not uncommon for this to be over 1kW hour per day (again depending on the particular unit and how it is used). One of the safest things you can do is run the intended refrigerator from a generator or even utility power if possible through a Kill-A-Watt meter and actually measure how much power it uses. Do not rely on information provided by the manufacturer.

    Also I am not sure if any of you are living in the mountains 1000m and above but wind speeds get higher the higher you are up the mountains.

    Well I for one am at 1000 meters. The wind up here is just the same as anywhere else; turbulent from trees and mountains. If you were out on the flat prairies you'd be better off as there are as many things getting in the way of the moving air. On the up side the insolation on the panels is higher so you get more power out of them. On average my system runs 82% from the panels whereas the typical norm is 77%.
    My last load will be a really high-powered power resistor. If anyone has any plans on how to make a DIY water heater with its own heating elements which shut off if the temperature is too high, that would be very help. Thermostat and high power relay sounds good and i wanna see how to properly configure such DIY water heaters.

    This is not the way to look at it. You're trying to find a place to dump excess power before you even know if you've got any. Better plan a system first before you decide what to do with surplus power.

    As far as it goes, electric water heating for a dump load is not a complicated thing. Proper wind power regulation can be though. The best equipment available now for this is MidNight's Classic & Clipper.

    But again you are not at the stage to be worrying about this.
  • bill von novak
    bill von novak Solar Expert Posts: 891 ✭✭✭✭
    Re: Windmill Dump Load Alternatives - How to set up multiple DIY water heaters?
    crystaleye wrote: »
    My last load will be a really high-powered power resistor.

    That works as long as it's rated for the max power your wind turbines can produce.
    If anyone has any plans on how to make a DIY water heater with its own heating elements which shut off if the temperature is too high, that would be very help. Thermostat and high power relay sounds good and i wanna see how to properly configure such DIY water heaters.

    I strongly suggest just using off the shelf water heaters, elements and thermostats. Once you have that you can add a few very simple components (relays) to complete the switching system.