Titanium Geyser Element: Solution To Reduce Your Hot Water Consumption By 50%?

[richardpickering]

Thanks for the Welcome Andy D. I am not an expert as many of you on this forum clearly are. I am only an accountant and software guy, 12 months into the renewable space.
Obviously the Econocoil claims are bold. I have yet to meet anybody, myself included, who is not massively skeptical. Hence the fact that we are measuring performance in peoples homes. We only listed the product once we had the field results in. Lab results are consistent, but only lab results.

Every engineer I know has said it is not possible, or it is possible, but not to such a degree. We will be collecting more measured information as we install more units.
We are using water and power loggers on the geysers to ensure that data is available. If there is anybody on this forum who has a 150 or 200 l horizontal Kwikot I would love to offer you a free trial (with full metering) so we can get your views. We operate in Cape Town.

I will post additional results here as I get them. I would value anybody's input. Essentially I have evidence to date that it works. I need more as we will only sell something to our customers that does what it claims.
Essentially the point i think that is not being discussed sufficiently is that there is a big metal plate on the Kwikot. This loses far more hear than any other part of the geyser. Moving the heating process as well as the hot water from this point has a significant impact.
You are right to be skeptical. Who wants to test it out?! Free.

[SilverNodashi]

I agree with Andy on this, these claims are probably just "fancy sales pitch". The 40% savings is far too much in my opinion. In fact, I don't see how this can save any money at all, regardless of the fact that it's a bit further away from the metal plate. Doesn't make any sense at all. I would have been happy to run a trail, but I guess the best way to run a proper trail, would have been to have two identical geysers, with identical plumbing, and then take out say 100L of both at a time, and then record the energy used and time needed to heatup to the same temperature, say 60 degrees Celcius.

[richardpickering]

Folks, there is not a single engineer who believed the claims. We have converted many, who remain a bit baffled. I only care about the numbers, I have no engineering skills to throw at the problem.
I can only assure you that we will not deliver a sales line that is not backed up by measured proof. We are in the process of field testing. We will install metering equipment (power and water) with the next 10 customer installations.
The claims are crazy. We had the same reaction. I am happy to share the lab test results and the results from the field. These follow the tests that you have outlined above. In our tests we tested different draw off profiles, but all over a 24 hour period, even if there was only 1 draw. We also measured the exit temperature of the water from the tank at the end and adjusted for temperature differential.

In the field we have measured a week of use with standard coil and then our one. This is obviously the test than counts and we need to see how the savings compare in different use-cases.
We are continuing with these tests and will publish them all on the website. We will only officially launch the product in Jan 2017, assuming that the results from our field tests continue to verify what we have found in the lab.
If anybody on this thread is in Cape Town and would like to be included in the tests then I am happy to do this. If you are converted you can buy your Econocoil. If not we will remove all the equipment, return your original element and publish your results with the rest of the ones that we collect.

[SilverNodashi]

Folks, there is not a single engineer who believed the claims. We have converted many, who remain a bit baffled. I only care about the numbers, I have no engineering skills to throw at the problem.
I can only assure you that we will not deliver a sales line that is not backed up by measured proof. We are in the process of field testing. We will install metering equipment (power and water) with the next 10 customer installations.
The claims are crazy. We had the same reaction. I am happy to share the lab test results and the results from the field. These follow the tests that you have outlined above. In our tests we tested different draw off profiles, but all over a 24 hour period, even if there was only 1 draw. We also measured the exit temperature of the water from the tank at the end and adjusted for temperature differential.

In the field we have measured a week of use with standard coil and then our one. This is obviously the test than counts and we need to see how the savings compare in different use-cases.
We are continuing with these tests and will publish them all on the website. We will only officially launch the product in Jan 2017, assuming that the results from our field tests continue to verify what we have found in the lab.
If anybody on this thread is in Cape Town and would like to be included in the tests then I am happy to do this. If you are converted you can buy your Econocoil. If not we will remove all the equipment, return your original element and publish your results with the rest of the ones that we collect.

So, please explain to me, how exactly do you get more efficiency out of an element? 40% in your case? Crunching the numbers, it means a 1Kw element only need 600W to heat up the same amount of water, over the same time period to the same temperature, or 1200W on a 2KW, or 1800W on a 3KW element!

[Justloadit]

Their is a finite amount of energy required to heat up a litre of water, irrespective of the method used. In some instances the cost of energy due to the type of energy may cost more or less. In this case we are referring to a resistive element used to transfer the heat generated by the element to the water. This is called specific heat

Specific heat is a physical property of materials. It is used to describe heat transfer. The specific heat of a material is an intensive property that is independent of the amount of a substance. It is defined as the amount of energy needed to heat one gram of the substance by 1 degree Celsius. The mathematical expression is Specific heat = calories / grams oC

Specific heat is essential when designing engine cooling systems, constructing electronic circuits so they do not overheat, designing refrigeration equipment and everything that involves heat transfer.

The amount of heat needed to increase the temperature of any object can be figured using this relationship.
Heat in calories = mass in gram x temperature change oC x specific heat [ cal / gram oC]
The formula has four terms in it. You can calculate any of them if you have the other three.

So how can a resistive element be more efficient than another resistive element when fed with the same amount of energy?

What may not be disclosed here, is that an intelligent device is connected to the geyser, which then uses an algorithm to calculate when power is applied to the element. This then will give you the types of electrical savings as claimed, but simply changing an element of the same value to another of the same value WILL NOT SAVE YOU ENERGY. Adding a geyser blanket and cladding pipe work is another means of reducing standing losses.

I think that the whole story is not being published.

[SilverNodashi]

Their is a finite amount of energy required to heat up a litre of water, irrespective of the method used. In some instances the cost of energy due to the type of energy may cost more or less. In this case we are referring to a resistive element used to transfer the heat generated by the element to the water. This is called specific heat


So how can a resistive element be more efficient than another resistive element when fed with the same amount of energy?

What may not be disclosed here, is that an intelligent device is connected to the geyser, which then uses an algorithm to calculate when power is applied to the element. This then will give you the types of electrical savings as claimed, but simply changing an element of the same value to another of the same value WILL NOT SAVE YOU ENERGY. Adding a geyser blanket and cladding pipe work is another means of reducing standing losses.

I think that the whole story is not being published.

Unless current geyser element are really very inefficient, and this version has improved on the design?

[Justloadit]

An element which is a meter long and 2KWatt, or 300mm long and 2Kwatt, will still produce the same amount of heating energy, the only difference, is that the temperature along the longer element may be less at the surface area than the shorter element, BUT this does not mean that the shorter element is more efficient in heating the water than the longer element, what it would do, if you were using it to heat barley or some other organic material, is to burn on the surface of the shorter element any organic material. Water is not organic, and therefor makes no difference at what temperature is on the surface of the element, the heat will be absorbed by the water, and will pass on to the cooler parts of the geyser, thereby equalizing the total temperature through out the vessel. If there are temperature differences, then this would be due to lost heat to the environment at the points where the temperature is lower.

[AndyD]

......Essentially the point i think that is not being discussed sufficiently is that there is a big metal plate on the Kwikot. This loses far more hear than any other part of the geyser. Moving the heating process as well as the hot water from this point has a significant impact......

I'm not an expert on Kwikot 150 litre geysers but I will be in the next few days because I have an old one in my workshop that was left in the roof space by the bone idle lazy plumbers who replaced it under warranty last year and the first time I get a chance it will be disected on my workbench.

Reading between the lines here I'm guessing the big metal plate you're referring to may be an internal baffle inside the cylinder perhaps.

Any components inside the cylinder, including any metal plates, will have heat losses but those losses are determined by two things, the temperature difference between the internal cylinder and the surrounding environment and the quality of the insulation that surrounds the cylinder.

If there is an internal baffle plate then altering the length of the element could have a profound effect on the circulation of the water inside the geyser whilst it's being heated. It could have an effect on the temperature gradient between water at the bottom of the cylinder and water at the top. It could even result in a large percentage of the water in the cylinder remaining cold or cool due to lack of circulation during heating.

Regardless of the numerous possibilities one thing is certain, if the geyser is consuming less electricity with the new element arrangement then it's producing less hot water. Yes, the water that comes out when a tap is turned on may be at the same temperature that it was with the old element but there will be less of it available so during high demand times the geyser water will become cold sooner. You're effectively taking a 150litre geyser and turning it into one that only produces 120 litres or maybe 100 litres of hot water. Could it produce electricity savings? Maybe it could but I still doubt it would be even remotely close to the 40% claims and if its a family of four or five people there's a good chance a couple of them will be taking cold showers.

However you wiggle and jiggle the element in a geyser, any savings will be at a cost, you'll always end up robbing Peter to pay Paul.

[richardpickering]

Thank you all for the active feedback. I am not yet certain of the savings and we are doing field tests. Once complete I will share the results either way. Signing off until I have more information back from the field. We will not be selling this to a soul if the evidence in the field does not continue to back up the numbers from the lab.
WRT to the last point about less hot water, the lab tests include emptying the geyser and measuring the the average water temperature to add back/subtract from the other power measurements for remaining energy in the geyser. I will bug you all no more until I have more numbers.

[SilverNodashi]

It would be worthwhile to log all data, i.e. ambient and internal water temperature, energy used / consumed, and water disposed / re-filled during the test periods.

[richardpickering]

Econocoil Update

Hi Again

We have just launched this product to market. Please see www.econocoilsa.co.za for the test reports and video. I know there are many skeptics borne of many unfulfilled promises of efficiency.
I would value your expert feedback on our information.

Our field tests delivered an average of 33% saving. This was in 5 separate homes. We measured water flow through the geyser and power using an effergy meter on the element line. The tests were done for 2-4 weeks with the standard element & Econocoil.

I look forward to taking heat from you again!

Cheers
Rich

[AndyD]

None of the links on the website to the Skeg full 20 page report work, I tried Firefox and Opera so I'm guessing it's a website technical issue.

[richardpickering]

Thanks Andy. Dumb error on website. Thank you for picking it up. It is now fixed.

[Dave888]

I still don't understand how this element can save this much electricity. As many posts have mentioned, Q=mCp(T1-T2), so heating m litres of water by y degrees will require a defined amount of energy. The only variable will be the heat losses.

The website states that the energy saving is achieved by mixing the water inside the geyser more efficiently, dropping the temperature in the top section by say 20 deg, which then leads to lower heat transfer. I agree, and a quick calculation will show that the reduced heat flow of an insulated section at 60 deg vs 80 deg is about 28%. But then the temperature of the whole geyser is higher, and losses will be higher over the entire surface of the cylinder, not just the top section. So I suspect savings are not very significant.

Heat loss depends totally on the insulation of the geyser tank and the temperature of the surrounding air. Geysers manufactured to SABS standards are controlled in terms of their standing heat loss and the insulation requirements are regulated by SANS 151. The maximum allowable heat loss for a 150lt capacity geyser (most common geyser size) is 2.6kW per 24 hours at a stored water temperature setting at 65 degrees C and no water is drawn off during the 24 hour period. This translates to a temperature loss of between 10 to 12 degrees C over the 24 hour period. If 150litres uses 8,7kWh to heat from 20 to 65 deg, standing losses are less than 30% (in my opinion, still much too high).

You would get a 31% saving in heat losses simply by doubling the thickness of the insulation.

The maximum saving by dropping the temperature in the top section by 20 degrees may be (optimistically) around 0,5kWh per day. Say 15kWh per month (= R30 to R40 pm). The average house uses 30kWh per day, so the total saving will only be about 1,5% of the total bill.

BTW, an Xtreme non-ferrous geyser (which is very well insulated) has a temperature drop of about 1 deg/24hrs, so is a lot better than a conventional steel geyser.


Secondly, stratification in a geyser is actually a good thing - it allows the use of the hot water from the top of the tank, while fresh cold water flows into the bottom, and is not allowed to mix with the hot water. This is why many geysers have baffles - specifically to prevent mixing of hot and cold.

[Justloadit]

OK downloaded the report.
I noted an error on table 3, 2nd line, Volume - 30L standard element temperature shows 30, I suspect that this should be 60 Degrees.

I also noted that Under Apparatus it shows that the Econocoil is 3.0KW and the standard element is 3.0KW, however in 5.1 Appendix 1: Heat Distribution Test it shows the Econocoil as 2.0KW and standard element as 3.0KW

I will need time to study the report, just do not have the time right now.
Depending on the Econocoil rating, it may have an influence on the how one interprets the results.
I think I understand what the position of the econocoil is doing, by it's position, improving the distribution of the heat of the water in the geyser due to natural convection movement of heated water, as opposed to the element in the centre.