Solar Powered Homes

[Art Deco]

A cistern is a tank. I am not aware of any issues regarding the different metals. All the electrical circuits are sealed and weathertight, and have fuses by code when installed, so I think you are OK.

 

[Cassy0110]

I've recently installed off grid solar system Renogy 400W I have LED lights combined draw 15amps. The battery monitor shows how many hours of battery are left at the current draw. Even after days of clouds, and the monitor gets down to 30% or so, it only takes a couple of hours to bounce back to 100%. On clear days and all lights on, it would show that I have 40 hours of battery left.

 

[kevinmccune]

Hi Tom. I think that tax credit can be applied across several years but I haven't looked it up; and I also think it is more generous now then it was a decade ago.
But remember that a solar home needs all the cheaper, easier stuff first to work well: like efficient appliances, extra insulation, efficient HVAC and water heater, etc. Budget for those things, and you may find you need a smaller solar system. And then the financing and tax breaks matter a lot.
The shopping is even worse than buying your first eBike if that's possible.

Amen, how abouts lights, entertainment and one refrigerator?(hybrid system)

 

[kevinmccune]

By cistern, do you guys just mean a water tank?

ALL our roof water is collected / stored in a 90,000 litre water tank ( corrugated galvanised / painted iron tank with a food quality liner ensuring that 20 years of watered down bird s*it can ferment in peace ) . That's our home water supply - we filter as much bird s*it as possible out of it before drinking.... Our roofs are all colorbond ( painted corrugated steel) .

My concern is not the water / bird s*it quality - I know enough microbiology to chuckle when people start discussing gut microflora diversity....

I'm more worried about any physical issues eg are there particular gutter designs to reduce the risk of water damage to the panels / magic smoke tubing ( wires) , any concerns with dissimilar metal galvanic corrosion between your typical solar panel and the average gutter material?

You can make an excellent solar water heater using galvanized roofing( how about an attic water heat booster, the sun is good at heating things a large percentage of our electricity is used to heat water.)

 

[PDoz]

You can make an excellent solar water heater using galvanized roofing( how about an attic water heat booster, the sun is good at heating things a large percentage of our electricity is used to heat water.)

I've already got an adequate solar hot water system - evacuated tube from about 20 years ago, still doing a good job.

I was more interested in the logistics of water catchment when I extend my solar electricity array ( preparing to move to electric vehicles and charge ourselves) . nb this is our household water supply - everything from drinking to flushing the toilet. So I was interested to explore the logistics of water catchment directly from solar electricity panels - eg preferred gutter types , can the gutters be mounted directly to the panels or do they need independent supports ( 25 metres of gutter holds a lot of water during heavy rain ) . Is there a way to water seal between panels so we catch water efficiently? Any pitfalls others have experienced that we can avoid?

I realize the simplest option is just build a large metal carport for water catchment then put the panels above it. But it just feels environmentally wasteful to build a metal roof if we don't need to ( if the solar panels can be the roof itself) .

 

[kevinmccune]

Seems to me you are overthinking this, a pretty good water filter is not that hard to construct and if you miss a few raindropds so what , if you are going to drink that water never mind the worms, small animals and bird output, pollen put a UV treatment on there.The best use for the PV array would be for shade rather than shedding water, you could always use Mr.Musks solar shingles if they are still in production, when I build a carport or shed I always overbuild rather than building to a minimum. My last carport would easily hold any solar system I would care to put on it. If you are building a huge array I would imagine the cost of the roof itself would be a fraction of the total array.

 

[PDoz]

Seems to me you are overthinking this, a pretty good water filter is not that hard to construct and if you miss a few raindropds so what , if you are going to drink that water never mind the worms, small animals and bird output, pollen put a UV treatment on there.The best use for the PV array would be for shade rather than shedding water, you could always use Mr.Musks solar shingles if they are still in production, when I build a carport or shed I always overbuild rather than building to a minimum. My last carport would easily hold any solar system I would care to put on it. If you are building a huge array I would imagine the cost of the roof itself would be a fraction of the total array.

Sure, but over thinking saves issues compared with under thinking.

eg We've just lost 40,000 litres of water and faced a $4.5 k repair bill due to a copper pipe that leaked within our concrete slab. The builders ran the pipe directly through the slab rather than in conduit, so we couldn't simply slide new pipe through the conduit. Ie $50 of conduit would have saved us $4 k if we knew 20 years ago that builder was dodgy.

re your uv suggestion - it doesn't help reduce particles, so we still get premature wear on moving parts ( taps etc) . It also doesn't help with corrosion of the copper pipes - between the rotting bird sh1t and the times we've had ash from bush fires contaminate our water....lets just say a 90,000 liter battery isn't a good idea.

One filter from our drinking water tap

 

[kevinmccune]

Makes one wonder why a smaller pipe couldnt have been ran thehrough the existing one( maybe cut flow down too much,BTW it was common practice to intall copper in concrete.)If I had water that nasty I would haul drinking water.

 

[indianajo]

We've just lost 40,000 litres of water and faced a $4.5 k repair bill due to a copper pipe that leaked within our concrete slab. The builders ran the pipe directly through the slab rather than in conduit, so we couldn't simply slide new pipe through the conduit. Ie $50 of conduit would have saved us $4 k if we knew 20 years ago that builder was dodgy.

Every builder does it that way. The copper to iron pipe junction is inside the wall. That connection corrodes. Wife filled up her basement with city water from such a leak, 900 cuft a month since she wasn't reading her bills on autopay. I use 100 cuft a month, but she didn't ask me, she asked her son about high bills. The city condemned her house calling the water in the basement sewage. Cost $22000 to make her house livable again.

 

[PDoz]

Every builder does it that way. The copper to iron pipe junction is inside the wall. That connection corrodes. Wife filled up her basement with city water from such a leak, 900 cuft a month since she wasn't reading her bills on autopay. I use 100 cuft a month, but she didn't ask me, she asked her son about high bills. The city condemned her house calling the water in the basement sewage. Cost $22000 to make her house livable again.

Around here, the copper pipe is continuous and runs inside plastic conduit . I suspect our copper pipe was laid at the very last minute, and laid directly to avoid an extra trip into town for supplies - we had experienced heavy rain leading up to when they poured the slab which restricted access to the site . They had been dumping large blue rock as a driveway right up until the concrete truck arrived ( and getting lines of 4x4 builders utes bogged in the gloop trying to pull each other out ) . Entertaining.....

 

[J.R.]

Around here, the copper pipe is continuous and runs inside plastic conduit . I suspect our copper pipe was laid at the very last minute, and laid directly to avoid an extra trip into town for supplies - we had experienced heavy rain leading up to when they poured the slab which restricted access to the site . They had been dumping large blue rock as a driveway right up until the concrete truck arrived ( and getting lines of 4x4 builders utes bogged in the gloop trying to pull each other out ) . Entertaining.....

If it's Type K copper pipe, distinguished by green print on the actual pipe, then you couldn't have had a better grade of pipe. Type K, 3/4" pipe has a wall thickness of .065 inches and is designed for underground use. Portland cement will not corrode copper unless they used a mix containing cinder or fly-ash. that would be very uncommon for modern floor slabs.

 

[indianajo]

Portland cement will not corrode copper unless they used a mix containing cinder or fly-ash. that would be very uncommon for modern floor slabs.

The problem is between a copper pipe indoors, and a steel pipe outdoors. That makes a galvanic battery, and in water it will corrode. Wife's house was built 1953, junction in concrete wall started leaking 2016. Nothing to worry about, 63 years, right?
New pipe was put in copper from the meter. The meter is steel. I hope the plumber put some galvanic barrier at the joint. He made a special trip to MasterSupply in Louisville to get it, since he had at the job the wrong size. If not a galvanic barrier it will make a pool in the yard 64 years from now, not fill the basement with water. Interior plumbing is now Pex (plastic).

 

[6zfshdb]

Lately, around here, I see contractors using PEX pipe in poured concrete. So far, it seems to work but It's too new a practice to know if there will be problems down the road. A cheap form of insurance would be to use oversized PEX in the concrete. That way, a smaller pipe could be inserted later if there is a problem.

 

[kevinmccune]

Around here, the copper pipe is continuous and runs inside plastic conduit . I suspect our copper pipe was laid at the very last minute, and laid directly to avoid an extra trip into town for supplies - we had experienced heavy rain leading up to when they poured the slab which restricted access to the site . They had been dumping large blue rock as a driveway right up until the concrete truck arrived ( and getting lines of 4x4 builders utes bogged in the gloop trying to pull each other out ) . Entertaining.....

Been my experience(construction veteran) Concrete truck drivers have a perchant for hitting soft spots( of course the weight and lack of manuverbility could be contributing factors)

 

[kevinmccune]

Lately, around here, I see contractors using PEX pipe in poured concrete. So far, it seems to work but It's too new a practice to know if there will be problems down the road. A cheap form of insurance would be to use oversized PEX in the concrete. That way, a smaller pipe could be inserted later if there is a problem.

Good idea hard to implement, I believe PEX has the same expansion coefficient as CT. Pex is used in radiant slabs.

 

[kevinmccune]

The problem is between a copper pipe indoors, and a steel pipe outdoors. That makes a galvanic battery, and in water it will corrode. Wife's house was built 1953, junction in concrete wall started leaking 2016. Nothing to worry about, 63 years, right?
New pipe was put in copper from the meter. The meter is steel. I hope the plumber put some galvanic barrier at the joint. He made a special trip to MasterSupply in Louisville to get it, since he had at the job the wrong size. If not a galvanic barrier it will make a pool in the yard 64 years from now, not fill the basement with water. Interior plumbing is now Pex (plastic).

I have seen iron roofing react with its zinc coating( under the right conditions- stacked in the weather, be careful how you store.

 

[PDoz]

Sorry for the threadjack - it sounds like building techniques vary significantly between Aus and the US , so any Re catching water from solar isn't going to apply here.

Unfortunately most local companies building solar carports are more interested in catching electricity than water, but I'll keep asking the locals and hopefully find out more.

Meanwhile, back on topic - we had an energy audit done at work recently. I was surprised they felt the time for cost neutrality on replacing halogen lights with led made +/- upgrading an infrequently used water heater made more sense than sinking those $ into solar generation. ( 3 year payback vs 6) . I suspect that has more to do with our feed in tarrifs +/- energy prices, but EMOTIONALY I want to sink the $ into solar rather than just replacing lights / water heaters.

 

[kevinmccune]

Sorry for the threadjack - it sounds like building techniques vary significantly between Aus and the US , so any Re catching water from solar isn't going to apply here.

Unfortunately most local companies building solar carports are more interested in catching electricity than water, but I'll keep asking the locals and hopefully find out more.

Meanwhile, back on topic - we had an energy audit done at work recently. I was surprised they felt the time for cost neutrality on replacing halogen lights with led made +/- upgrading an infrequently used water heater made more sense than sinking those $ into solar generation. ( 3 year payback vs 6) . I suspect that has more to do with our feed in tarrifs +/- energy prices, but EMOTIONALY I want to sink the $ into solar rather than just replacing lights / water heaters.

Solar has a glamour of its own, it works pretty good around here where the utility wants 50K$ to run a feeder line.( what would you do?)