This listing was down for a month as I was on vacation, but I'm back and we still have three sets of 50 tube units ready to roll. Solar glass vacuum tube water heaters. (full 1800mm tubes including frame and manifold not the "mini" toy type). These are low-pressure evacuated tube collector (ETC) systems. What "low pressure" means is they are meant for use with swimming pool or jacuzzi pumps or hot water circulating pumps.
They are not meant to be directly connected to the main water supply at full pressure. They do not have heat pipes. The water flows directly into the glass tubes. I have two units left for sale out of the original six I was hoping to sell as a unit for a swimming pool.A single 50 tube set of ETC tubes like this one converts 3.5kW of thermal energy on a clear sunny day. If you wanted to replace that with PV panels it would require fourteen 250 watt panels to replace one single 50 tube ETC system. This ETC solution is not only more powerful and compact than PV, it is much lower in cost and allows more options in terms of mounting angles and involves no electronics other than the existing pump. Think about the no electronics part when considering the options.
Busted electronic controls are a gravy train for pool and spa repair shops. I had to raise my price a bit because of the Trump tariffs.
This product is on the tariff list and the price went up 35%. The fifty tube sets give you much more bang for the buck. Total power is 70W per tube so 50 tubes is 3.5kW of thermal output in full sun. How much is that in hot tub terms? I can list some examples.
Let's use 500 gallons as our hot tub size. One single 50 tube unit would raise the water temperature from 75F to 85F in two hours. Do keep in mind that solar thermal works best in clear skies. If you're in a foggy place this might not be the most appropriate choice. If you're inland though, this solution is definitely going to be cheaper and more efficient than using PV solar with a heat pump.Glass solar collectors 1800mmX58mm borosilicate glass. Header tube (where the hot water flows) stainless steel. Outlet = stainless 1" NPS male thread (DN 25 OD 1.3.15"). For more info on the thread please look up the phrase "Nominal Pipe Size". Typically used with a storage tank/heat exchanger and electric hot water pump.
Storage tank and pumps not included. Using a 15 tube unit we have been able to heat a six person jacuzzi to around 110F with no additional energy input on sunny days starting around April on the Central Coast of California using a 90 watt circulating pump. That was in the summer but it was also just fifteen tubes.50 tubes is powerful heat source when combined with a small pump or wired straight into the hot tub pump. Tip: To estimate the heat concentration of a vacuum tube system use 70W per tube. So, ten tubes would be 700 watts of heat in full sun. Fifty tubes would be 3.5kW thermal energy. That is an abundance of energy conversion going on all day while the sun is shining. These units get hot enough to produce steam under normal use. Glass is a whole different game than a coil of plastic tubing. Power is one thing though, t. He real magic is that you can store that energy as hot water. Free fuel plus low-cost storage equals the most appropriate renewable technology for hot tub and pool heating.
From the sky to your nice hot tub with no bills and no contracts. If you're in a sunny desert with clear skies, these things should perform exceptionally. On the Central Coast of California they produce steam easily. New in box, imported from China.
One of the largest solar tube manufacturers in China. I'm an authorized distributor for California. Feel free to ask any questions or make an offer. Location is off 101 freeway between LA and San Francisco at the intersection of Santa Barbara and San Luis Obispo Counties.
The boxes weigh around 280lbs total per 50 tube set and come in the following dimensions. (width X height X length in inches).13 X 7 X75 glass solar tubes (X3 boxes of 10). 7 X 7 X 96 metal manifold + accessories. 6 X 5 X 93 metal frame + accessories.
None of the boxes is over fifty pounds except the frames. The frames for the fifty tube units are quite heavy at around 80lbs.
For swimming pools, the factory recommends at least 20kW or 300 tubes for small in-ground pools around 5000 gallons. You need a lot of tubes to do a good pool heating job and it has been cost prohibitive in the past but I think that even with the tariffs and other associated costs of importing them these designs are already low cost because other heat sources are not free either.
Go straight to the source in terms of energy and store it in your pool. It's between you and the sun. The down side is that these things are indeed massive and heavy and fragile. For a single unit or two pretty much any truck and many vans will do. The tubes are about six feet long so if you stack two wide in each of these 50 tube vertical manifolds and add some space for the manifold you're talking about a square at least seven feet by thirteen feet.This vertical manifold design is a cool new trick. When you're plumbing into this you can add a drain valve if you like. That's one way that these horizontal units can be easier to maintain for a pool where you're directly running the pool water into the glass tubes.
I know there are so many pools out in the desert that would be great with solar heating and get lots of bright sun on cool winter days. Places in the desert with 5000 gallon swimming pools are really what I'm thinking of as a target market but no matter what the location is very key point is whether you really have space for these things. A jacuzzi seems like an obvious fit. If you have or if you know of someone who has a pool that has a nearby south facing wall or a large adjacent area with sun exposure during the day this could be an ideal pool heating solution.These tubes work at all different angles and can even be hung on a vertical wall. A bit of trivia for interested readers. These tubes are also sometimes called "thermal diodes" because the heat can only flow in one direction. The tubes are also called "frequency converters" and that's quite literally a description of how they work. The coating on the inside is not just black paint but actually is a kind of cermet (ceramic + metal) semiconductor (aluminum nitride) which converts UV light to Infrared (heat). Visible and UV light are converted to infrared on the inner layer of the selectively coated innter glass tube. Borosilicate glass used in vacuum tubes is relatively UV transparent down to around 330nm. The aluminum nitride UV frequency converter coating is very thin and if the tubes break the inner-tube can still be used for glassblowing by removing the aluminum nitride layer.
An easy way to do that is by scraping. This item is in the category "Home & Garden\Yard, Garden & Outdoor Living\Pools & Spas\Pool Equipment & Parts\Pool Heaters & Solar Panels". The seller is "ahfooo" and is located in this country: US.This item can be shipped to United States.