What's the latest on solar hot water heaters?

[KTurner]

In the solar PV class I took earlier this year we were discussing solar hot water heating. The instructor, who is a strong supporter of solar, was waffling on the economics of solar hot water heaters because the price has gotten so high. I think he said that a system was around $7,500 but it might have been higher. NC has a MAXIMUM subsidy of $1,400 for solar water heaters. If I qualified for the maximum amount, and I was using $30 of power a month to heat water, it would take 16.9 years to get my money back on the system. I raised the question in class if would it be better to us PV to heat the water since panels are pretty danged cheap. $7K buys quite a bit of PV power.

An advantage of using PV to heat your water compared to a solar hot water heater is that you would just use whatever electric hot water heater you wanted to buy. If you had a few weeks of clouds like we just had, we would still have hot water since we would still be grid tied, and the hot water heater would not know or care if the power was from PV or the power company.

Like (removed) said, you can make a solar water heater out of lots of things, even scrap wood and pipe. Pretty hard to do things like that for PV. Your ROI is pretty darn quick if you build it out of mostly scrap or extra hoses/pipes you have laying around. You could even just hook up and throw some dark colored coiled up water hoses out in the sun to heat up the water in them - need more capacity, just add more hose. That might be a workable solution for a rarely used low draw low cost system (with some sort of anti-scald valve) like with the OP was looking for. Plus, it'll be the low on the "that looks worth stealing" scale (unlike an array of shiny new PV panels).

I still need to hook up some clocks to find out how much electricity is going through my water heater elements so I can figure out if its worthwhile for me.

Keith

 

[Larry Caldwell]

There are plans for effective solar collectors all over the internet. Even buying new materials, you can build one that will provide hot water for a family of 4 for only a few hundred dollars.

As for heat pump reliability, mine has been running for 17 years, with only one service call to replace a starting capacitor. Heat pump reliability mostly depends on an absolutely perfect installation. Buy a bucket of solution and clean the coils once a year.

 

[user.69169]

Thing is in 2013 we're living in a world of people who got a hunk of paper hanging on their wall says they smart. Little problem comes up that piece of paper didn't make them smart enough to think through, they get to talking about the problem like wimmen do. Got this place called Internet and they let their fingers talk posting on some web site.

Just like a bunch of wimmen they post up less than half of the problem so there ain't a hope of solving, but it sure do get other wimmen to wagging their fingers. Next thing ya got some woman typing away about how her car don't run even though she cranked the key over for 10 minutes. Probably would have saved some time if she'd noticed the gas gauge said the gas tank is EMPTY.

Fact is a man living in Mississippi pretty much got about 15 ways to make hot water from the Sun at his shop building for less money than $100 if he's willing to do a little work. He don't need no expert, he don't need no panel sitting on the roof or in the yard, and he dang well don't need to worry about it freezing more than about once every 10 years.

You dang sure didn't see salesmen running house to house selling water heaters when I was a kid in Louisiana, people had them hot tanks up there in the attic or what should have been the attic.

 

[forgeblast]

Go Sunward - Solar Hot Water Made Simple. was the direction we were looking on going. I need to save up for the project first though. If you want to do it yourself check out garygarys site at builditsolar.com