I've been in this industry 13 years. We have been doing full solar geysers with its own tank on the roof, as well as retrofit pumped solar geyser conversions. We also do this ac dc element conversion. A few facts in this video are a little bit misleading. 1 - The benefit of a integrated solar geyser(like the one in this example), is that it needs no electronics. If there is sun, there will be hot water. (It does have an element fornrainy days though, but can be installed without it). Sizing is of utmost importance though. 2 - It's true that they can overheat but we have replaced a negligible amount of valves and rubbers and have installed thousands of systems. If done properly, its no more maintenance than a standard geyser. In fact,our stainless steel tanks will far outlast conventional geysers. 3 - This AC/DC system performs much worse in overcast weather than any vacuum tube system. It has its place in the market, but cost vs benefit is not always worth it for domestic use.
Is it at all possible to retrofit a very old low pressure geyser? When I say very old, the house was built in the sixties and we bought it in the eighties. The geyser has never given us problems - not even once. But now we must find ways to save on the electricity bill. Thank you for a neat, well--made instructional video.
A typical household needs hot water mainly in the morning, say from 5am - 6am. That means the geyser should have been heating water from at least 4am. But we know that around that time, there is no sunlight, therefore you'll have to use the grid. It is the same thing in the afternoon when people come back from work. That is between 6pm - 8pm. I expect the solar panels to have heated the water already during the day but depending on the demand (the number of people), you may have to draw from the grid because the sun will not be available for solar to heat up extra (refilled) water after the first use. Therefore this system is useful in the evenings after the solar panels had had a chance to produce electricity but not so useful at the critical part of the day, that is, in the morning. To meet the evening demand, maybe the capacity of the geyser can be expanded. But the rest of the system should be expanded as well (solar panels). I think for this system to improve availability and efficiency, we need to devise ways to store large quantities of hot water for longer so that the system can heat up and store enough water (for morning and evenings) during the day while the sun is out. Alternatively, we can use batteries to store energy for later morning geyser use, but this is an expensive solution.
thats why a battery pack is crucial to store power that will be used whenthere is no sunlight for panels to do thier thing....when the sun comes out it will be to replenish the pack and you will be good to go
200l water heated to 65c can last both evening and morning use for 4 people. The amount of water your geyser can take/heat also makes difference in how long the water will stay hot. Its also a form of storing energy the more you can store the longer it will last. You can test this by turning off a normal geyser at 18:00 have the family use the geyser both night and the next morning If the hot water lasted both cycles, this will work without the grid. But as stated amount of people vs Liters of the geyser.
the water tanks themselves are heavily insulated and can hold temps pretty well over night, but it's not a 100% solution, thats why they are AC and DC elements so that if you need it you have the grid and can be switched, the goal is to reduce grid use, not be off grid.
Great viewing. I have the system installed however there is an disadvantage not discussed. During loadshedding the system does not work so i loose 2 to 4 hours of "solar time" to heat the water in the geyser.
I’m also here to learn but there shouldnt be any inverter or batteries. DC element would heat off DC power from the solar panels and MPPT solar controller directly. So it stays DC power all the way and therefor no inverter required for AC conversion
Both systems make use of the sun's radiation i.e. reference to sun's heat is incorrect. It is just that the evacuated tubes use more of the spectrum of sun's radiation which makes it more efficient than the pv system. The tubes also have a built-in stagnation temperature which is a safety mechanism against run away tempertures. Evacuated tube system is cheaper, lower cost and simpler compared to pv system
Why not just produce AC power with your panels through an inverter? That way you heat water when needed and when it’s hot enough you produce electricity for other needs, instead of having panels doing nothing.
I hear doing a retrofit on a geyser isn't recommended because theres more risk of a geyser burst occurring? Because the solar panels can make the element burn hotter than recommended? How do you remove that risk?
This would apply if there were no thermostat. This product has a thermostat connected to the MPPT. When the water reaches the set temperature, The MPPT will not allow the power to go through to the element. I hope tis answers your question.
because pv system for whole house is closed to 5kv system which cost r35k min and runs on batteries which runs out quite quickly. this system doesn't require batteries which will continue to power the element until the pre-set temp is reached and instructs the mppt to switch off. my 5c advise to anyone is invest gas stove/oven, solar geyser or in this case pv conversion kit and maybe a 1k or 2k pv system with battery running the rest like tv, computer, wifi, lights etc for at least the period loadshedding takes place. this will work much cheaper out
No tim im doing this for years but on a manual basis. I have to switch off my solar heating before 11 12 to curb over heating.. im also going to go to automatic control the 2 systems
Compare to your conversion kit system the solar geyser is at least 30-50% cheaper in terms of material. So in other words evac tubes, controller and 220v pump R8000. this i found in cpt. Installation cost should be about R1500-2500 EXCL COC. i had solar evac tubes geyser system and never had any problems at all. i would suggest 220v circulation pump instead of that 12v since the 12v becomes faulty and causes overheating. Your system on a 200l geyser with 4 panels acdc element mppt etc all at 15k. So you are incorrect at the start of your video saying it is more expensive to purchase and install the solar geyser than your system. the only way whereby the conversion kit works and is a clear winner is that it is basically a diy and maintenance free that's it! with that being said, I have to admit the conversion kit is much better and convenient and i would advise anyone to go for it but, we have to be honest with viewers/customers too that it is in no way cheaper!!!
Interesting new concept however the newer indirect pumped systems seem to have overcome the issue of water boiling during hot days/low usage. I have had two of these systems, each one for 12 years and never had any issue with tube leaks. I fitted a Y strainer before the circulating pump and cleaned it regularly for reliable trouble free operation.
I am looking at these systems. I have 2 geysers in my House. The primary reason for installing this is to save electricity on a standard Geyser what are the savings I am looking at per month? What's the down side of this system if there are any? How long will it take this DC element too warm up a 150 litre geyser? What company installs these systems? Are there any use cases of people who actually installed this type of system and what savings they have seen? Sorry for all the questions.
It takes about 5 hours of full son in summer to reach 50 deg Celsius. I did an experiment on it and gathered some data here. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-_xClSxBWfqs.html
