 Notice. New forum software under development. It's going to miss a few functions and look a bit ugly for a while, but I'm working on it full time now as the old forum was too unstable. Couple days, all good. If you notice any issues, please contact me. |
Forum Index : Other Stuff : Water pressure Pumps
| Author | Message | ||||
| VK4AYQ Guru  Joined: 02/12/2009 Location: AustraliaPosts: 2539 |
Hi All Like a lot of you I live in a rural area and rely on tank water for household use. I was out shopping a few weeks ago and came across a digital timer with a built in watt meter, I decided to see what various items use in watts per 24 hours, quite interesting. I tried it on my pressure pump and found that it used 1500 watts a day for normal household use and 2500 watts on washing day. total 12500 watts per week on average. This included a five minute watering of the house garden each evening. At local electricity all inclusive cost this is $3.50 a week or $180.00 a year. I decided to set up a 12 volt pressure pump and after raiding the store cupboard and a trip to the hardware store I found enough bits and pieces, total cost including the pump $120. Half a days work and a bit of re plumbing it was working. While it isn't the flow capacity of the pressure pump it is enough for normal use the other half hasn't winged about it so it must be allright. I used the old 12 volt system I had on the roof already that runs odds and ends and keeps my car and emergency battery starter charged. The two old panels are over 20 years old and deliver 5 amps on a good sunny day. It was fitted with a 20 amp regulator that cycles to equalisation every morning then floats at 13.4 volts for the rest of the day, after two weeks use all is working well and it equalises the batteries by 10:30 am on sunny days and 12:30 on overcast days, after normal overnight with showers toilet and washing up the batteries are still on 13 volts in the morning, all in all a good success, and brownie points from the missus as when the power goes out we still have water. All the best Bob Foolin Around |
||||
yahoo2 Guru Joined: 05/04/2011 Location: AustraliaPosts: 1166 |
There is a crowd that is selling a 100 litre water pressure tank on ebay. I have been thinking of buying a couple of them to try out. I understand it will cut the power usage right down because the pump is not continuously starting and drawing a high load. I'm confused, no wait... maybe I'm not... |
||||
Gizmo Admin Group  Joined: 05/06/2004 Location: AustraliaPosts: 5078 |
When I bought my place in Mackay it only had a jet pump running of grid power, meaning if the power goes out, so does the water. To me thats crazy, especially in a bush fire prone country. I had a hill behind me, so mounted a 1,000 litre tank about 10 meters above the house. I kept it topped up with a combination of 12v pumps and a farm windmill, and used gravity to feed the house when the main jet pump was out of action. So I always had water, even if the grid power went down. My new place is pretty flat, so I would need a tower to lift a tank high enough for good pressure. So instead I've put in two water supply systems. One uses a small 300 watt 240vac pressure pump that came with the house. Its powered by a BP Sinewave inverter, rated at 300 watts. This uses a couple of 12v batteries, kept charged up by a couple of 70watt solar panels. The 12v system also powers some yard lights all night long, draws about 1.9 amps at night, and is fully recharged by about 10am next day. The BP inverter must have a good surge rating, it has no problem starting the pump. The 2nd system uses a much larger 240vac Davey pressure pump ( thanks Phill ), draws about 700 watts running. It's power from the big inverter and 50volt battery bank. Both systems have their own water tanks, 10k liters for the small pump, and 20k liters for the big pump, and the pump outlets feed a common supply to the house and yard taps. So if one system falls over, the 2nd system will take over and supply water. The big pump has a higher pressure setting, so its working most of the time. If I want to use water from the other tank, I just switch one pump off at the power point. I'm using one tank for house, and the other when I water the plants, washing cloths or squirting the dog. Glenn The best time to plant a tree was twenty years ago, the second best time is right now. JAQ |
||||
| VK4AYQ Guru Joined: 02/12/2009 Location: AustraliaPosts: 2539 |
Hi Yahoo I had one of those on the original system with about 25 litres and it discharges 9 litres before the pump starts, I hate to think what it would have used switching on and off all the time. All the best Bob Foolin Around |
||||
| VK4AYQ Guru Joined: 02/12/2009 Location: AustraliaPosts: 2539 |
Hi Glenn That's a good system, with two back up. I have a similar system but the 240 volt pump is in series with the 12 volt pump, the 12 volt pump sucks through the 240 volt pump and if I need more water or pressure I can switch the 240 volt unit on. I did it that way as I only have one tank source 2 x 30 K Ltr set up connected to the shed roof, when I can afford a new tank for the house I will dual system like yours, the old tank has cancer, and I have cancer of the wallet so won't happen soon. It is amazing what a couple of panels can power if you use the energy efficient equipment. I liked the hill method you had up north, unfortunately no hill here and the cost of building a tall tank stand is a real issue, another job for the future. All the best Bob Foolin Around |
||||
| VK4AYQ Guru Joined: 02/12/2009 Location: AustraliaPosts: 2539 |
Hi All I got some photos to show the set-up ,it is a hay wire set-up as the first thing was to prove the concept. 
The pressure tank is a 20 Litre unit and it delivers around 9 litre of water. 
The regulator is swinging on the wire at the moment, I am going to mount on the wall, the volt and amp meters are just to monitor what is happening and the sequences of the regulator. The batteries are the ones I recovered a couple of years ago (battery rescue) and still going OK this application is making them better as the light cycling on the pump is better than sitting on the main battery bank, I am using desulphators on the batteries. The smaller battery is out of a gen set that sat for 12 months and was rescued also, it is a gell cell so it shows they can be used as well. I also used the battery to run my radio and CB. I run a lead to my car battery to keep it alive as it doesn't get enough use to keep it charged and it is running all sorts of things in the car all the time and the Jaycar desulphator also draws power all the time and helps to it to go flat. The other red jump starter battery is kept on here as it used a bit of mains power through it's plug pack charger, of course I forget to plug it in most times so the jump starter was at times to flat to work properly. 
The pressure controller I used was one of an old pressure pump, it has three contact sets rated at 11 amps AC so I connected all three in Parallel to make it last longer on DC, so far it is working and visual on the points doesn't show any arcing, so hopefully it will last. Set to shut off at 1.5 bar and cut in a .8 bar, it will work higher but draws more amps 7 amps as compared to 4 amps as set now. All the best Bob Foolin Around |
||||
| yahoo2 Guru Joined: 05/04/2011 Location: AustraliaPosts: 1166 |
Finally found what I was looking for. Collyn Rivers has written about using pressure accumulator tanks. He observed with a 500 litre pressure tank fitted the standard 750 watt pump ran for 3 to 4 minutes once or twice a day. That's probably maximum 60-100 watts a day? If the pump can be triggered to run in the afternoon when the batteries are close to fully charged ( to top the pressure up before the evening water use), then most days there would be no load from the pump on the batteries.  Of course there is always a catch, 500 Litre pressure tanks are not given away in cornflakes packets are they.
Myself, I run an overhead tank, that is very economical on power, the pump runs for 30 minutes every 1-2 months. The water system I have is designed around the water heater, a vented low pressure hot water tank. If I didn't have this, there is no way I would use the overhead tank. Every fitting, tap, shower head, washing machine, dishwasher, water filter, etc etc etc, has to work with low water pressure. It really limits my options when I want to replace or upgrade something I'm confused, no wait... maybe I'm not... |
||||
| VK4AYQ Guru Joined: 02/12/2009 Location: AustraliaPosts: 2539 |
Hi Yahoo You are right the cost of large accumulators would take 20 years to save the equivalent amount in electricity, by then it would be rusted out and would need replacing. I am thinking of trimming the top off a large tree beside the house and putting a 500 ltr tank on top of it, that would give me 14 Lb,sqin of about 1 bar if you are metric about the same as I have now with the present set up. It works the shower and the washing machine OK. Another project for another day. All the best Bob Foolin Around |
||||
| Riverduk Newbie  Joined: 16/09/2013 Location: AustraliaPosts: 6 |
Hi Bob, just came across this post and even though its a bit older now, what caught my eye was you mentioning the digital timer that you purchased. What brand is it? where did you get it from and cost (approx.)? I am just starting down the road with off grid renewable power and need to make some calculations with regards to power usage of current pumps we have on our property so I can work out a starting point for my power storage and generation requirements. Cheers Ross |
||||
| VK4AYQ Guru Joined: 02/12/2009 Location: AustraliaPosts: 2539 |
Hi Ross I purchased the power meter from the local Crazy Prices store it has a timer to turn load off and on and a sub menu to read the power used, total and term while it was on. About $15 from memory also available on Fleabay not branded so I can't help there. All the best Bob Foolin Around |
||||
Downwind Guru Joined: 09/09/2009 Location: AustraliaPosts: 2333 |
You can make a general calculation by working out how long the pump will run for in hours for a 24 hour period. Look at the Watts rating of the pump is and times it by the hours, then divide it by 1000 to get Kwh for the day. Pete. Sometimes it just works |
||||
| Riverduk Newbie Joined: 16/09/2013 Location: AustraliaPosts: 6 |
thanks both Bob and Pete, I did a bit more searching after I left this post and have discovered they are out there everywhere, just need to know what to look for, seem to start at about $20 these days and according to a Choice article the cheapies work as good as the more expensive ones, so Jaycar, here I come. With regards the calculations, I don't know about your guestimations but mine can be pretty well major ball park most of the time, I reckon for $20 it would money well spent to get a better pic of usage of each device, Cheers, Ross |
||||
| VK4AYQ Guru Joined: 02/12/2009 Location: AustraliaPosts: 2539 |
Hi Ross They are a handy tool to try all your electrical appliances, HWS and flat screen TV are the worst wasters on a normal use but heating and cooling are are real killer. All the best Bob Foolin Around |
||||
 Print this page |
