Living offgrid with small solar system(s)

[George Harmony]

From the water coming in. The ram pump must be lower than the water source.you can see clearly in this vid that the watersource, in this case a watertank, is a bit higer than the pump.

In my case as explained above i can try do dig a hole and put the pump there and from 1m deep connect a pipe to the top of the pond. Perhaps it will also work underwater in the pond. Pipe goes downwards to the pump which is situated much lower in the pond.

Edited May 16, 2016 by George Harmony

[George Harmony]

Explanation ram pump

https://m.youtube.com/watch?v=Zk9zs0EQIQ8

[Naam]

George. Where is the energy coming from to pump the water??

for a ramp pump to work *** you need the energy of high flow combined with high head. anything else is an over*wet*unity dream.

***with efficiency***

Edited May 16, 2016 by Naam

[George Harmony]

George. Where is the energy coming from to pump the water??

for a ramp pump to work *** you need the energy of high flow combined with high head. anything else is an over*wet*unity dream.

***with efficiency***

There are also linear ram pumps where you indeed can get wet high above and not only from a wet dream.

@naam,perhaps you never been to villages with no water supply at all whereby children go with buckets to get water from creeks. Ive seen with my own eyes that a small amateuristic ram pump pump the water from the creek to the village. The difference between the watersource and the ramp pump was i think no more than 1 - 1.5m. The village lies about 50-60m higher than the creeks and the ramp pump.

Example linear ram pump:

Edited May 16, 2016 by George Harmony

[Crossy]

There is no argument that ram-pumps work, they do and well.

BUT

They cannot be over 100% efficient, the energy of 1kg of water falling 2m will only pump 0.1kg of water to 20m (if it's 100% efficient, and it's not), the other 0.9kg goes to the waste port.

They do a good job of converting low-head high flow to high-head low flow. If that's what you need great

[Naam]

The village lies about 50-60m higher than the creeks and the ramp pump.

over*wet*unity perpetuum mobile dream

[George Harmony]

And @naam here is another boring (test) ram pump youtube vid. If you ignore that such small ram pump does not work from a bucket on a chair or table than i must conclude that you are stubborn hahahahaha

Edited: If i want to use ramp pump to water my roof...the pump shown in the vid is more than enough. Also the flow per liter as long as my roof get wet and refresh over and over again. Dont need a lot of bars pressure.

Edited May 16, 2016 by George Harmony

[Crossy]

And @naam here is another boring (test) ram pump youtube vid. If you ignore that such small ram pump does not work from a bucket on a chair or table than i must conclude that you are stubborn hahahahaha

Edited: If want to use ramp pump to water my roof...the pump shown in the vid is more than enough. Also the the flow per liter as long as my roof get wet and refresh over ans over again. Dont need a lot of bars pressure.

How many gallons per minute did it actually pump?

We don't see, only that it USED 0.8 GPM to produce a trickle at the top of the outlet pipe.

Enough now of the baiting, I will close this thread if it continues!

[George Harmony]

There is no argument that ram-pumps work, they do and well.

BUT

They cannot be over 100% efficient, the energy of 1kg of water falling 2m will only pump 0.1kg of water to 20m (if it's 100% efficient, and it's not), the other 0.9kg goes to the waste port.

They do a good job of converting low-head high flow to high-head low flow. If that's what you need great

10ltr of water with 10m head can pump 1 ltr per second 100m high....right???

[George Harmony]

From pumps to inverters.

Is it possible for for example my planned wok cooking during peak hours to connect pv (array) directly to an inverter since most of the inverters have a max input of 15volt??

Here is a company that claims to have such an inverter. Anyone have experience with such inverters??

http://www.cyboenergy.com/solutions/pvsolarcooking.html

[Crossy]

There is no argument that ram-pumps work, they do and well.

BUT

They cannot be over 100% efficient, the energy of 1kg of water falling 2m will only pump 0.1kg of water to 20m (if it's 100% efficient, and it's not), the other 0.9kg goes to the waste port.

They do a good job of converting low-head high flow to high-head low flow. If that's what you need great

10ltr of water with 10m head can pump 1 ltr per second 100m high....right???

Wrong.!

But I get the feeling you know that and are playing with us.

[Crossy]

From pumps to inverters.

Is it possible for for example my planned wok cooking during peak hours to connect pv (array) directly to an inverter since most of the inverters have a max input of 15volt??

Here is a company that claims to have such an inverter. Anyone have experience with such inverters??

http://www.cyboenergy.com/solutions/pvsolarcooking.html

Look elsewhere for inverters with higher input voltages (up to several hundred volts).

From your link:- System generates 1.15kW peak and can supply heating elements up to 3000W (3kW). Right!

Batteryless inverters are available from multiple suppliers, but none can output more than they are supplied with.

[KonaRain]

C'mon Naam, tell George that sprinkling his roof is the best thing the physics world has invented so he will quit.

Tryin to read all these, I need some solar panels..to charge phone..

I have a metal roof, with 2×6 toungue and groove..they put two layers of medium weight tar paper between wood and metal.

Then if I lived in a (lower) warmer area, celing fans seem to be the state-of-the-art. I've been checking the restaurants in Kailua Kona and ceiling fans are the s...

You Men of course would use solar panels to power them.

Also, powering solar water heating is only 20% effective ,using photovoltaics, compared to water panels,

water sandwich of course for heating.

20% compared to what?

Aloha, Gentlemen

[Naam]

Look elsewhere for inverters with higher input voltages (up to several hundred volts).

From your link:- System generates 1.15kW peak and can supply heating elements up to 3000W (3kW). Right!

Batteryless inverters are available from multiple suppliers, but none can output more than they are supplied with.

isn't it possible to increase output if super capacitors are used Crossy?

joke aside, a serious question: "is it possible to build an inverter "bank"?

[Crossy]

Peak output, possibly https://en.wikipedia.org/wiki/Supercapacitor

If you mean running multiple inverters in parallel, yes, provided the inverters are designed to work that way.

It's also possible to use a small pure-sine inverter to trick a grid-tie inverter into starting up and supplying power (Google AC-coupled solar), handy to get things going if the grid is off and the sun is shining.

[George Harmony]

There is no argument that ram-pumps work, they do and well.

BUT

They cannot be over 100% efficient, the energy of 1kg of water falling 2m will only pump 0.1kg of water to 20m (if it's 100% efficient, and it's not), the other 0.9kg goes to the waste port.

They do a good job of converting low-head high flow to high-head low flow. If that's what you need great

10ltr of water with 10m head can pump 1 ltr per second 100m high....right???

Wrong.!

But I get the feeling you know that and are playing with us.

Although i went the best gymnasium in holland i did choose the alpha and not beta side and have nearly no knowledge of physics. About ram pump with 100% efficiency see attached pict.

About the inverter, thanks for your valuable reply. I think they mean max capacity of 3kw. Not sure though. Otherwise they must be more stupid than me to promote their product like this hehehehe

Edited May 17, 2016 by George Harmony

[Crossy]

Without a battery or supercap array for energy storage there is no way for a 1.1kW solar array to drive a 3kW load, at least not in this universe.

I know perfectly well how ram-pumps work. Please explain how your nice diagram equates to efficiency. By their very nature ram-pumps waste a huge amount of the water that goes in, it's energy is extracted and then it goes to the drain, the energy is then used to lift a much smaller volume of water to a greater height.

As noted earlier they convert low-head high-flow to high-head low-flow. Provided you have a limitless (and free) low head supply (creek or small dam) they do a remarkably good job.

[Naam]

If you mean running multiple inverters in parallel, yes, provided the inverters are designed to work that way.

that means 'run-of-the-mill' inverters can't be used?

[Crossy]

If you mean running multiple inverters in parallel, yes, provided the inverters are designed to work that way.

that means 'run-of-the-mill' inverters can't be used?

Correct.

But do look at AC coupled systems which use multiple grid-tie inverters and a small off-grid unit to get the system started.

[Naam]

If you mean running multiple inverters in parallel, yes, provided the inverters are designed to work that way.

that means 'run-of-the-mill' inverters can't be used?

Correct.

But do look at AC coupled systems which use multiple grid-tie inverters and a small off-grid unit to get the system started.

i just wanted to make a test with gadgets that are available in my workshop without any serious plans for actual use.

[George Harmony]

I know perfectly well how ram-pumps work. Please explain how your nice diagram equates to efficiency. By their very nature ram-pumps waste a huge amount of the water that goes in, it's energy is extracted and then it goes to the drain, the energy is then used to lift a much smaller volume of water to a greater height.

As noted earlier they convert low-head high-flow to high-head low-flow. Provided you have a limitless (and free) low head supply (creek or small dam) they do a remarkably good job.

As i stated above the diagram = 100% efficiency. For professional made ram pumps this is the usual standard:

Water Delivered = Available Water x Source Fall x 0.5 ÷ Delivery Height

Lets just conclude as you did that ram pump CAN be very effective to lift water to much higher elevation with a 24 hours operation with no fuel nor electricity nor human nor animal power

About using inverters without batteries. Very interesting posts of @crossy. Thanks.

[Crossy]

No machine can be 100% efficient.

From your formula:-

For example:- An inlet flow of 100 L/s @ 10m head will deliver 10 L / s @ 50m lift.

Using PE (Potential Energy) rather than KE (Kinetic Energy) to make life easier (just looking at the end static conditions) we can get;-

Input = Potential Energy of 100kg (100 L of water) @ 10m head = mgh = 9,800 Joules (g=acceleration due to gravity=9.8 m/s²)

Output = Potential Energy of 10kg (10L of water) @ 50m head = 4,900 Joules

Efficiency Input/Output x 100% = 50% (evidently where the 0.5 in the formula comes in to play)

Compare with a hydro electric turbine = 80-90% energy conversion, or a simple undershot water wheel = 60-70% energy conversion. Not very efficient, but it scores in a big way for simplicity.

As you say, time to leave this one alone

[IMHO]

Peak output, possibly https://en.wikipedia.org/wiki/Supercapacitor

If you mean running multiple inverters in parallel, yes, provided the inverters are designed to work that way.

It's also possible to use a small pure-sine inverter to trick a grid-tie inverter into starting up and supplying power (Google AC-coupled solar), handy to get things going if the grid is off and the sun is shining.

I'm guessing all a grid-tie inverter needs to see is an AC waveform within it's own operating frequency range? I can't imagine anti-islanding works by looking at voltage, otherwise you'd never be able to have parallel grid-tie inverters.

[Crossy]

Everything you need to know about island protection

http://www.digikey.com/en/articles/techzone/2015/jun/anti-islanding-and-smart-grid-protection

https://cdn.selinc.com//assets/Literature/Publications/Technical%20Papers/6381_AntiIslandingToday_VM_20100527_Web.pdf?v=20151125-092432

[Gary A]

I was using my grid tie inverter to supplement my off grid inverter. The grid tie was fooled into working by the off grid inverter. I noticed that when the batteries were topped up and the grid tie was producing more power than I was using, the off grid inverter was acting strange. The cooling fan was going on and off. I always unplugged it when that started to happen. I guess that I was too late unplugging the grid tie inverter when the off grid inverter went bang. Dead. i was glad to have a spare inverter and since I got three years out of the blown inverter, I didn't feel too bad. I have since bought another spare. I took the covers off the inverter that went bang and couldn't see anything that looked burned. If I can find someone to check it out, it may be repairable. The grid tie inverter is now back feeding the grid. Using the grid tie to feed the off grid works but I discovered that you need to make sure you are actually using the extra power.

[George Harmony]

Very easy and efficient (small)solar setup with capacitor directly connected to an inverter without using battery.

https://m.youtube.com/watch?v=yyMM6a0D6q0

Go to 3minutes+ to see how this guy set it up.

[Crossy]

I was using my grid tie inverter to supplement my off grid inverter. The grid tie was fooled into working by the off grid inverter. I noticed that when the batteries were topped up and the grid tie was producing more power than I was using, the off grid inverter was acting strange. The cooling fan was going on and off. I always unplugged it when that started to happen. I guess that I was too late unplugging the grid tie inverter when the off grid inverter went bang. Dead. i was glad to have a spare inverter and since I got three years out of the blown inverter, I didn't feel too bad. I have since bought another spare. I took the covers off the inverter that went bang and couldn't see anything that looked burned. If I can find someone to check it out, it may be repairable. The grid tie inverter is now back feeding the grid. Using the grid tie to feed the off grid works but I discovered that you need to make sure you are actually using the extra power.

Sad to hear that

Unfortunately inverters are not designed to sink power so you need a means to absorb extra (or cut off the panels) once the batteries are full.

The popped unit should be repairable, Amorn Service seem to be able to fix almost anything.

[Gary A]

I was using my grid tie inverter to supplement my off grid inverter. The grid tie was fooled into working by the off grid inverter. I noticed that when the batteries were topped up and the grid tie was producing more power than I was using, the off grid inverter was acting strange. The cooling fan was going on and off. I always unplugged it when that started to happen. I guess that I was too late unplugging the grid tie inverter when the off grid inverter went bang. Dead. i was glad to have a spare inverter and since I got three years out of the blown inverter, I didn't feel too bad. I have since bought another spare. I took the covers off the inverter that went bang and couldn't see anything that looked burned. If I can find someone to check it out, it may be repairable. The grid tie inverter is now back feeding the grid. Using the grid tie to feed the off grid works but I discovered that you need to make sure you are actually using the extra power.

Sad to hear that

Unfortunately inverters are not designed to sink power so you need a means to absorb extra (or cut off the panels) once the batteries are full.

The popped unit should be repairable, Amorn Service seem to be able to fix almost anything.

To be totally truthful, the old inverter had a noisy cooling fan. (even when new) The replacement is even more oversized than the one that popped. It has two fans that seldom run and when they do run, they are very quiet. It was worth buying a new one to eliminate the noise. I am not able to determine how efficient it is because my Fluke meter only has one decimal place. I do know that comparing the AC output amps to the DC input amps tells me it is more than 100 percent efficient. Yes, that is impossible. I paid extra for a Fluke because I thought it would be more accurate than the cheap multimeters. Maybe that isn't the case. The old inverter gave me three years without any problems so it doesn't owe me much if anything. I'll have Amorn take a look at it and if a repair is cheap enough, I'll have two spares. Since the fan is noisy, I don't really care if it gets repaired or not. It sits just over a meter from my computer.

[Jing Joe]

Ram pumps. Clever invention. Not important how efficient. They work. Agree to disagree gentlemen.

I recall being in a small discussion and stating 746 watts in one horsepower at a friends dinner party. One guy disagreed, I proclaimed I could be wrong, but he wanted to prove me wrong and actually left in the middle of dinner and drove home to go check his current study book.

He returned perhaps a little red faced but I couldn't have backed down enough beforehand. Just saying guys.

Forty one pages and hardly an argument. There must be gentlemen here and Crossy says keep it that way. :-)

There must be more pump designs than fish in the sea.

Has anyone seen or used the design where many turns of black ploy pipe are neatly wound around and fixed to say a 200 litre drum, it has bearings on a axle through the axis.

The axle has a rope at each end tethered cross-ways to the flow in a stream. Paddles attached to the drum turn the half submerged drum and the open end of the poly pipe collects water each time it dips into the water.

The other end of the poly pipe has a rotating connection with an O ring, that passes the pumped water up hill or wherever.

Not as simple as the ram pump but takes advantage of the flowing water, not a small head.

The air locks in undulating cross country pipes can have disastrous pressure challenges and I wondered if this has been turned to an advantage in this "pump".

I'm Guessing Naam might be the first to throw light on some of this design??

Edited May 18, 2016 by Jing Joe

[Jing Joe]

I was using my grid tie inverter to supplement my off grid inverter. The grid tie was fooled into working by the off grid inverter. I noticed that when the batteries were topped up and the grid tie was producing more power than I was using, the off grid inverter was acting strange. The cooling fan was going on and off. I always unplugged it when that started to happen. I guess that I was too late unplugging the grid tie inverter when the off grid inverter went bang. Dead. i was glad to have a spare inverter and since I got three years out of the blown inverter, I didn't feel too bad. I have since bought another spare. I took the covers off the inverter that went bang and couldn't see anything that looked burned. If I can find someone to check it out, it may be repairable. The grid tie inverter is now back feeding the grid. Using the grid tie to feed the off grid works but I discovered that you need to make sure you are actually using the extra power.

Gary; this thought may not be relevant but keep in mind there are dodgey electrolytic capacitors in many units. When they go bang the indented x shaped relief points in the end of the cap open slightly when suddenly releasing pressure.

Quite frightening too. Cant remember the one offending brand (and maybe others) but many such faults happened in the last 10 years??. Google it?

Before this innovation, they quite exploded and did damage to nearby components and the offender was VERY visible.

I had one go bang in my variable bench power supply and mightn't have easily discovered what happened except for the tell-tale mark close by on the inside of its case. Good luck.

BTW are you aware of the beautiful fans available now? Brush-less, Magnetically coupled and magnetic levitating bearings. Jay car catalogue could be a starting place. Hope this helps.

Edited May 18, 2016 by Jing Joe