If it wasn't for the adventure . evacuated tube system -- long post

[mkel]

MKel-solar1.jpg
I haven't posted here in quite a few years -- last time was with our adventures with freezing heat tubes. My system is 80 evac tubes that was on the roof and made a lot of hot water until the heat tubes started freezing. A bunch of us posted a lot of discussions about repairs of tubes etc. I repaired all of mine several times but over time they failed again. My supplier sent me 80 new heat tubes and I didn't have much faith that they would be better than the ones that failed. I put them in a walk-in deep freezer at -10 degrees for a week and none of them failed. so maybe all that is behind us. Anyway ... Life got busy and I never installed the heat tubes and my system has been running at maybe 40% for the last 5 years or so. Still plenty of hot water as when it all 80 tubes worked I had too much hot water and set the system to dump at 180 degrees to avoid blowing things out..
NEW STORY...
Well this year a bad storm tore the crap out of our house, roof and solar tubes. Of course the insurance company depreciated the crap out of everything and would not cover anything on the solar. Fortunately my supplier is the best and he hooked me up with everything I need to get it back going. But I had to take the entire system off the roof so the roof could be replaced. so ... 80 tubes - up and down for each tube is 160 trips up and down the roof and at 63 years old I'm NOT doing that again. Just about killed me..... House got a new roof installed and the solar is lying in pieces around the yard. (pic is of the original install)
SO WE GO AGAIN ...
Started by working on building ground mount frames and removing all the plumbing from the attic and then re-route all the tank plumbing to go into the crawl space and a bunch of plumbing to get to the best sunny side of the house... Next I'll get a backhoe and dig a ditch to run the lines in as the panels will be ground mounted about 75' from the house. I have to go under a sidewalk which I am sure is going to be a joy but it's part of the deal. I can't tell you how many times I thought I must be nuts and it isn't worth the trouble but I got some new ideas and the adventure of trying them is pushing me forward. Probably be a few months before I get it done... (have to before winter or it waits until spring)
For those that are interested I started taking some pictures as I go and will post them when it is finally operating ..
cheers, mike

[nwdiver]

MKel-solar1.jpg
I can't tell you how many times I thought I must be nuts and it isn't worth the trouble but I got some new ideas and the adventure of trying them is pushing me forward.

Well... enjoy your adventure. Do you have PV too or just thermal?

[mkel]

well right now I have a big pile of junk -- but I only had thermal.. I haven't tried anything PV yet. don't really understand it and it seems very expensive.
A guy up the street put in a 40 panel PV system to sell power back to the utility ... Until then I wasn't aware that the utility only pays for a percentage of kw the panels generate.
Since it isn't even close to the price he pays for electricity I wonder if the system will ever pay off in it's life.

I built my evacuated tube system in 2010 ... joined this forum in 2011 .. at that time there were a lot of people talking back and forth about evac tube systems.
A lot of experimenting went on -- I have to wonder how many of those people that built evacuated tube systems 10 years ago still have working systems today.

mk

[J.P.M.]

well right now I have a big pile of junk -- but I only had thermal.. I haven't tried anything PV yet. don't really understand it and it seems very expensive.
A guy up the street put in a 40 panel PV system to sell power back to the utility ... Until then I wasn't aware that the utility only pays for a percentage of kw the panels generate.
Since it isn't even close to the price he pays for electricity I wonder if the system will ever pay off in it's life.

I built my evacuated tube system in 2010 ... joined this forum in 2011 .. at that time there were a lot of people talking back and forth about evac tube systems.
A lot of experimenting went on -- I have to wonder how many of those people that built evacuated tube systems 10 years ago still have working systems today.

mk

As a %age of the evac. tube systems installed 10 yrs. ago that are still operating vs. the %age of PV systems installed 10 yrs. ago that are still operating, my educated guess would be that the %age for evac. tube systems is less. To the degree that's a statement that reflects some form of reality, part of the reason might be owners who are commonly unaware and/or don't perform the maint. or inspection of the evac. systems that are required to keep them functioning. They are not the type of system that can be ignored and expected to function as spec'ed.

[nwdiver]

well right now I have a big pile of junk -- but I only had thermal.. I haven't tried anything PV yet. don't really understand it and it seems very expensive.

I would encourage you to give PV a shot. I'm pretty sure the materials cost for most PV is now cheaper than evacuated tube thermal at least on a ROI basis. PV is DEFINITELY lower maintenance and from what I've seen easier to install.

I recently helped our electricity build out a system that will save him ~$70/mo for ~$3k. ~$2100 after incentives. Just have to shop around a bit and wait for some deals especially for panels. I regularly see panels for <$0.30/w and you can get a 'new' old grid-tie inverters for ~$0.10/w especially now that CA has rule 21 and some older inverters in inventory aren't compliant. That's how we got such a great deal on our electricians system. Each panel came with a free M215 Enphase inverter

Even if your utility doesn't give you full credit for your exports your system should still pay for itself in <10 years if you DIY. In your case I would install a smaller system unless you intend to get batteries. If you need ~10kW to offset 100% of your use get a ~5 or 6 kW system.