Author Topic: Wanting to get into solar? Think HOT WATER  (Read 28227 times)

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Offline Someone

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Re: Wanting to get into solar? Think HOT WATER
« Reply #75 on: May 12, 2016, 02:38:05 am »
With the low cost of PV panels, direct-solar HW systems are obsolete technology as far as I am concerned. Circumstances vary, but in many situations, mine included, you really would need to have rocks in your head to even consider installing a solar HW system.   

You need to provide some figures for this, and I think you will find that in the majority of cases the payback time for solar hot water is quicker than the system you are proposing.
Page 1 of this thread already has the numbers for electricity. Even using the inflated costs of a "professional installer" to setup the PV to hot water link its still very competitive:
https://www.ecoelectric.com.au/solar-hot-water-or-solar-pv/

Some other of advantages of Solar HW over PV hot water.
...
far less regulatory and safety issues/requirements/costs.
less safety issues/requirements.
I'd much rather work on a sealed electric hot water system and fiddle with its electricals than do plumbing on a pressurised steam system. And oh wait, working on the hot water system requires a licensed plumber while swapping the electricals on a plug in appliance (such as a hot water system) requires no license or permit. So the PV attachment to hot water is actually much easier and requires no licenses while plumbing does, the safety aspect is debatable and down to personal assessment.
 

Offline HackedFridgeMagnet

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Re: Wanting to get into solar? Think HOT WATER
« Reply #76 on: May 12, 2016, 03:18:31 am »
Sorry I didn't realise there were already some figures in this thread. Though as they are coming from a PV installer I doubt they are objective.

Even using these figures you should still consider it. Solar HW doesn't preclude a PV installation. If you have a look at the photo on https://www.ecoelectric.com.au/solar-hot-water-or-solar-pv/ you can see a combined installation. Notice the separate plane you can install the solar PV on. You might have a small section of roof no good for PV that you can use as a preheater for your HW.

I'd much rather work on a sealed electric hot water system and fiddle with its electricals than do plumbing on a pressurised steam system. And oh wait, working on the hot water system requires a licensed plumber while swapping the electricals on a plug in appliance (such as a hot water system) requires no license or permit. So the PV attachment to hot water is actually much easier and requires no licenses while plumbing does, the safety aspect is debatable and down to personal assessment.
I suppose if you keep the PV below 120V in you can do the wiring yourself, but most people in Australia have the grid connect system, so it is highly regulated. Those monetary figures are probably only valid for a CEC approved installation which is highly regulated, to the point of barcoding each solar panel and sending the details to the CEC.
It's not really more pressurised and not really a steam system. I like the indirect (heat exchange) versions where the HW tank is only barely above 1 atmosphere.
Another advantage of the heat exchange storage systems is that you don't have to worry about Legionnaires disease.

Actually after saying all that I should mention I am quite wary of the Solar HW system on my roof. I don't even go up there if it is boiling. 250l of boiling water is a bit scary.

« Last Edit: May 12, 2016, 03:27:09 am by HackedFridgeMagnet »
 

Offline Zeranin

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Re: Wanting to get into solar? Think HOT WATER
« Reply #77 on: May 12, 2016, 03:37:01 am »
Some other of advantages of Solar HW over PV hot water.

solar efficiency, probably 2 to 3 times pv per unit area.
True, though irrelevant unless roof area is scarce, as in your case.

works better than many PV systems when subject to partial shading.
Yes. PV systems need to sized to account for that, or in severe shading cases one must accept that PV is not suitable.

doesn't need planar alignment with other solar catchers.
This could be argued either way. With PV, it’s real easy to have two banks in different locations, connected to separate inputs on the inverter. That’s not a practical option with solar HW collector(s), as you really don’t want long, insulated hot water pipes running from here to there and back again – messy,expensive and thermally lossy. Electrical wires have got it all over fluid-carrying-pipes as a method of getting energy from one place to another, and wires don’t boil or freeze, either, and nor do they need a separate pump. Chalk and cheese. Electricity is the most high-quality, flexible, multi-use, easily transported source of energy available – nothing else even comes close.

far less regulatory and safety issues/requirements/costs.
less safety issues/requirements.
Sometimes, but often not. Some people have described very simple, safe low voltage PV HW DIY systems that are not mains connected at all, though in this case the overall utilization of the PV panels is poor. If you have or are getting a PV system anyway, then the regulatory and PV wiring stuff will be done anyway, and thus given that the 240V power will be there anyway, it’s much easier to install an electric HWS than a solar one. The DIY experimenter can make the electric HWS into an appliance by connecting a 3-pin plug lead (subject to the heater wattage being low enough) and simply plugging the HWS into a power point, a 15A power point if necessary. With this approach, the DIY experimenter can also build his own controller box for the electric HWS. The controller box plugs into a power point, and the HWS plugs into the control box.

Don't get me wrong I am all for PV and I just got my ticket for it, but all options should be considered.
Agreed.
 

Offline Someone

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Re: Wanting to get into solar? Think HOT WATER
« Reply #78 on: May 12, 2016, 03:38:13 am »
Sorry I didn't realise there were already some figures in this thread. Though as they are coming from a PV installer I doubt they are objective.
...
It's not really more pressurised and not really a steam system. I like the indirect (heat exchange) versions where the HW tank is only barely above 1 atmosphere.
Another advantage of the heat exchange storage systems is that you don't have to worry about Legionnaires disease.
The numbers on the first page of the thread are my easy calculation for rate of return, each person can determine the costs of the parts for themselves (as they very wildly) but as we keep going over a low voltage install is a great DIY project and can pay for its self in short order if you already have an electric hot water system. Given the lower upfront cost for supply/install of an electric storage system compared to a solar hot water system it becomes very hard to see how the direct solar hot water could be cheaper over its life.

Dual circuit systems are a great option, they could be useful in Australia for heating too if a energy dump exchanger were installed through the floor of living areas.
 

Offline MotorMagic

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Re: Wanting to get into solar? Think HOT WATER
« Reply #79 on: June 08, 2016, 02:28:17 am »
The website in the link seems a bit ridiculous. Just get a standard MPPT controller and be done with it, if you already use an electric water heater tank obviously you should also hook your solar system up to it. Where is the question? I wasn't even aware this was a revolutionary idea. I will say that I find it completely unexciting to just buy a couple panels to hook up to your water heater, advantage of PV is you can use that power for anything. If you only care about smoking up the shower there are a hundred ways to do it for pennies. If you really want to pinch pennies buy an electric kettle and take a bath in a bucket.  :scared:
 

Offline Zeranin

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Re: Wanting to get into solar? Think HOT WATER
« Reply #80 on: July 06, 2016, 06:48:01 am »
I have recently built a ‘PV Power Diverter’, which diverts my excess PV power to a 250 liter electric storage heater with 3.6kW element, that provides my entire hot water needs.

For those not familiar with PV diverters, a current xformer is used to monitor the net power flowing into the grid, and a triac is used to regulate the amount of power fed to the hot water (HW) heater such that only excess PV power is fed to the heater. In my case, using excess PV power in this way cost me nothing, because my feed in tariff pays me for every kWh of power generated, regardless of how it is used. More commonly, the feed in tariff is almost negligibly small, so it makes good economic sense to usefully use excess PV power for hot water, that would otherwise need to be paid for at a higher rate.

I live in Canberra, Australia, where the winters are moderately harsh, typically zero to -6 DegC overnight, though we do often get a run of clear days with daytime max of around 12 DegC. My PV installation has moderately severe shading issues in winter, but a lot of panels, so performance is probably equivalent to a 6kW system with little shading. The hot water serves 2 adults.

So how well does this PV hot water system perform? How often do I need to boost, and how does it perform compare to an evacuated tube system in the same city?

I have had it running now for around 3 weeks, in the middle of winter, and it’s very good indeed. On clear sunny winter days we run a 2.4kW (input), 7.2kW (heating) reverse cycle aircon all day to heat the 45 sqm living area, and there is still enough excess PV power to do the hot water without boosting, though only just. On cloudy/raining days we don’t use the R/C, and on most such days the cloud-shine and occasional appearance of sun also provides enough excess PV for the hot water. Without any PV input at all, the 250L tank, with setpoint at 80 DegC, will last for about 3 days. So far, we have not needed to boost, and I estimate boosting may be necessary around 4 days per year on average. I can ‘boost’ by choosing to draw power from the grid, or by using gas, but would choose gas because it’s cheaper and environmentally better than using grid power, though for a few days per year either is fine. It’s free hot water, for an initial capital cost of ~AUD$1000 for the 250L, stainless steel storage tank, plus my time and ~$100 of parts to build the diverter.

So how does this compare with an evacuated tube (ET) system? Turns out I have a good mate in Canberra with an ET system, and we know exactly how well his system performs, and how often it needs boosting, because his Resol solar HW controller logs all the key temperatures, and even plots them over a 30 day period on a web page. He started out with a 30 tube system, and it was pathetic, requiring very frequent gas boosting over winter. As he uses gas only for HW boosting, and the fixed costs of providing gas are $300 PA, he really wanted to eliminate the need for gas boosting and terminate his gas supply altogether, so he applied a ‘big hammer’ to the problem, and installed another 30 tubes, optimally pointed and angled for maximum winter performance. He has separate pumps for each bank of tubes, and his Resol controller is able to control both banks independently. That’s a 60 tube system, and optimally set up, at that! In summer he has to put black plastic over one bank, or the system will boil its brains out.

Even to my own surprise, the comparison is chalk and cheese. It’s been an unusually wet and cloudy winter here in Canberra, and when we get 2 or more days with heavy cloud and rain, the ET system just isn’t up to the task, even with 60 tubes, and gas boosting becomes necessary. Physics cannot be cheated. Even with 60 tubes, the collection area is still relatively small, and on days with little sunlight, the ET system can capture little heat energy, at best. But it is worse than that, because to prevent freezing at night, the tank water needs to be pumped through the collectors, destroying much of what little energy was collected. Also, the collection efficiency is very poor on cold, cloudy days, because on such days, the collector heat loss during the day is very significant compared to the amount of heat being collected. In contrast, PV panels don’t need defrost heating, and efficiency does not drop off under conditions of low temperature and low solar insolation, and nor does the efficiency drop off when producing water at high temperatures.

The practical result is that my PV hot water system leaves this 60-tube ET system for dead under all conditions. In summer, both systems have more than enough capacity, except of course that the excess PV power can be sold, or used for air conditioning or whatever. In the depths of a Canberra winter though, my PV system pumps out wonderfully hot water under nearly all conditions, when the 60-tube ET system has collapsed and needs significant boosting. I have had a lot of fun watching the day-by-day data plots of the water temperatures in this 60-tube ET system, and comparing with my PV system, and am quite surprised by just how much better the PV system performs. If you have the roof area, and are thinking about installing a PV system, then don’t waste your time with a traditional solar-collector HW system, with all of it’s additional complexity, freezing, boiling, and inferior performance that demands significant backup. Just add a few more kW of panels to your PV system, build or buy a PV power diverter, and take the PV hot water route. I’m laughing all the way to the bank. Hot showers never felt so good.

In warmer climates, or where roof area is scarce, or where you don’t have or want a PV system in the first place, the optimum choice may be different. Also, while for practical purposes I never need boost backup, that is with only 2 people. With a family of 4 or more, then my experience indicates that you will need some sort of boost backup with pretty much any solar HWS setup, at least in Canberra.
 
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Offline Zeranin

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Re: Wanting to get into solar? Think HOT WATER
« Reply #81 on: July 06, 2016, 11:58:53 pm »
To add some balance, I should point out that my mate’s 60 evacuated tube HW system works well by most measures. When averaged out over a full year, then it probably provides 80% to 90% of his total hot water energy needs, which on environmental or economic grounds makes it pretty good, but it does need significant boost backup in winter, while for practical purposes my PV HWS system does not, which was the point being made. His circumstances were unusual, in that he wanted to get off the gas completely, but couldn’t because his hot water storage tank has no provision for an electric heater, and he found to his cost that no practical number of tubes would remove the need for boosting over winter. His long term solution is to maintain his solar collector system, and replace the gas-boosted tank with an electric-boosted one. It’s been an expensive exercise, with first adding another 30 tubes, and then replacing the storage tank, but his final result should work well.
 

Offline mtdoc

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Re: Wanting to get into solar? Think HOT WATER
« Reply #82 on: July 07, 2016, 12:27:22 am »
Quote from: Zeranin
If you have the roof area, and are thinking about installing a PV system, then don’t waste your time with a traditional solar-collector HW system, with all of it’s additional complexity, freezing, boiling, and inferior performance that demands significant backup. Just add a few more kW of panels to your PV system, build or buy a PV power diverter, and take the PV hot water route. I’m laughing all the way to the bank. Hot showers never felt so good.
.

This echos what I was saying early in this thread. With PV prices so low, the equation has changed.

Sounds like you have a great system in place.  :-+

You might want to consider a heat pump hot water heater when your current one goes. I think you'll then find that even in winter, you'll never need to "boost" with grid power.

 

Offline Zeranin

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Re: Wanting to get into solar? Think HOT WATER
« Reply #83 on: July 07, 2016, 01:11:40 am »
Some thoughts re the importance of how a solar HWS is backed up. In Australia, where most of our power is generated from coal, producing hot water from grid power is environmentally very undesirable indeed, and this has interesting consequences for the overall environmental credentials of competing  HW systems. In order of ‘environmental badness’, HW systems can be ranked as :-

Conventional Electric Storage HWS  (worst by a long shot)
Direct Solar, with grid-sourced electric backup
Natural Gas
Direct Solar, with gas backup
DirectSolar, with diverted PV electric backup (equal best)
Solar PV, using 100% diverted PV power (equal best)

It might be thought that a Solar HWS is an excellent environmental choice, ‘obviously’ better than burning gas, but actually this is often not true. The second worse choice, on environmental grounds, is a Solar HWS backed up by coal-fired, grid-sourced electricity. The reason is that, as per previous discussions, unless you install a monster sized solar HW system, then significant boosting will be required in many climates, ruining the environmental credentials if the boosting is provided by coal-fired electricity. Generally speaking, 100% gas-fired HW systems are environmentally better than electrically-backed solar systems.

Solar with gas backup is an excellent environmental choice, but the initial capital cost is expensive. The gas backup is done with an instantaneous style gas heater, adding considerable cost over and above the solar HW installation.

The two equal-best options, from an environmental perspective, are Direct Solar with PV backup, and Solar PV, assuming in both cases that the PV system is large enough to provide all the electrical power needs, at all times of the year.

I haven’t ranked heat-pump systems, because I’m not sure exactly where they fit, but are generally ‘good’, and arguably best of all if the power is PV sourced. 
« Last Edit: July 07, 2016, 02:34:12 am by Zeranin »
 

Offline Zeranin

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Re: Wanting to get into solar? Think HOT WATER
« Reply #84 on: July 07, 2016, 02:10:11 am »
This echos what I was saying early in this thread. With PV prices so low, the equation has changed.

Sounds like you have a great system in place.  :-+ (It works for me ....)
You might want to consider a heat pump hot water heater when your current one goes. I think you'll then find that even in winter, you'll never need to "boost" with grid power.

Yes. With a heat pump, the electrical power required is about 1/3 compared to direct resistive heating, so without doubt I would never, ever need to boost, given that I hardly ever need to boost now.

Heat pumps can be wonderful, but in this case I decided that on balance I would prefer not. On straight economic grounds, I would be much worse off with the heat pump in my particular case, because already I have enough free excess power to provide all my water using resistive heating. So for me the operating cost would be the same, but the initial capital cost of the heat pump is much higher. On top of that, heat pumps are complex devices that are not always reliable, and have a definite lifetime, probably not more than 10 years at best. In contrast, my simple, low-tech stainless-steel electric hot water tank cost a modest AUD$1000, has no maintenance or reliability issues, and is expected to last at least 20 years. As it is, for practical purposes I never need to boost with my resistively-heated tank, so in my particular case there was no reason to get a heat pump, and many reasons not to. I do swear by my reverse-cycle aircon though, that heats my house for free on most winter days using PV power, and still leaves enough PV power left over to heat the hot water. Way to go.  :)
 

Offline jh15

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Re: Wanting to get into solar? Think HOT WATER
« Reply #85 on: July 07, 2016, 03:21:24 am »
Why heat hot water?
Tek 575 curve trcr top shape, Tek 535, Tek 465. Tek 545 Hickok clone, Tesla Model S,  Ohio Scientific c24P SBC, c-64's from club days, Giant electric bicycle, Rigol stuff, Heathkit AR-15's. Heathkit ET- 3400a trainer&interface. Starlink pizza.
 

Offline HackedFridgeMagnet

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Re: Wanting to get into solar? Think HOT WATER
« Reply #86 on: July 07, 2016, 03:44:43 am »
has no maintenance or reliability issues
FYI Hot water tanks are not completely reliable nor maintenance free. Especially if your water is hard. The tempering valves do fail. The elements and thermostats also fail.
Obviously these issues affect both Direct HW and PV hot water though.
I don't see how you can claim your system is lower maintenance when much of the stuff is the same.
I have done very little maintenance on my Solar HW system and it has been running a long time.

Also about your economics, and as it may apply to other people. If you use your house as an example you should include some of  the cost of your solar system which seems to be huge. (?10kw)

Freezing and boiling are not issues for me either. I have a 20 or 30 tube system, i bought it long ago so I cant remember.

These all point to the fact that so much depends on specific circumstances, so you should do a proper analysis before you design or choose your system.
When designing, often the difference between say 85% and 95% solar power is not worth the extra up front cost if you have effective backup.
Also if you DIY then be aware of the regulatory issues and how it could possibly effect your insurance.
In Australia only electricians should be wiring systems above 120V DC.

 

Offline HackedFridgeMagnet

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Re: Wanting to get into solar? Think HOT WATER
« Reply #87 on: July 07, 2016, 03:52:52 am »
I was thinking Zeranin that you should use your Hot water for Hydronic heating so you dont use the straight electric Heaters at night.
Just an idea.
« Last Edit: July 07, 2016, 05:07:42 am by HackedFridgeMagnet »
 

Offline Someone

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Re: Wanting to get into solar? Think HOT WATER
« Reply #88 on: July 07, 2016, 04:10:56 am »
has no maintenance or reliability issues
FYI Hot water tanks are not completely reliable nor maintenance free. Especially if your water is hard. The tempering valves do fail. The elements and thermostats also fail.
Obviously these issues affect both Direct HW and PV hot water though.
I don't see how you can claim your system is lower maintenance when much of the stuff is the same.
Except the direct solar systems have the same storage and pressure valves, and then a whole bunch of extra bits to go wrong that don't exist on the simple electric storage tank. The same with a heat pump, its replacing a resistive immersion heater (cheap and readily available) with a thermal engine that includes pressurised gas and heat exchangers. Its is entirely reasonable to say that the simple solution will be more reliable since it has fewer parts to fail and those parts are almost completely included with the alternatives.

In Australia only electricians should be wiring systems above 120V DC.
You've been shown to be wrong time and time again on Australian regulations. If its not hard wired into the grid or connecting a generating source to the grid you can do what you like, no electricians required. I've no exclusions in my insurance policy for building appliances or systems on my property or in my dwelling. The examples being suggested here as implemented as plug in appliances, or standalone DC systems.

You have direct solar hot water, thats fine. It was probably the most cost effective solution when you installed it. But times have changed and using PV to power hot water storage is now more cost effective, its less complex, and can be done as a DIY modification to existing equipment.
 

Offline HackedFridgeMagnet

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Re: Wanting to get into solar? Think HOT WATER
« Reply #89 on: July 07, 2016, 05:02:47 am »
You've been shown to be wrong time and time again on Australian regulations.
Ok you have made the statement, now point out where I was wrong time and time again.
 

Offline Someone

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Re: Wanting to get into solar? Think HOT WATER
« Reply #90 on: July 07, 2016, 05:31:50 am »
Some other of advantages of Solar HW over PV hot water.

far less regulatory and safety issues/requirements/costs.
less safety issues/requirements.

I suppose if you keep the PV below 120V in you can do the wiring yourself, but most people in Australia have the grid connect system, so it is highly regulated.

In Australia only electricians should be wiring systems above 120V DC.
All wrong. We are talking about modifying or controlling the hot water system, nothing to do with grid inverters, and no fixed mains wiring. This requires no regulatory oversight for a DIY project, no licenses, nothing. Stop perpetuating these messages, or show the regulations/legislation to which they would need to meet.
 

Offline Zeranin

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Re: Wanting to get into solar? Think HOT WATER
« Reply #91 on: July 07, 2016, 05:49:09 am »
has no maintenance or reliability issues
FYI Hot water tanks are not completely reliable nor maintenance free. Especially if your water is hard. The tempering valves do fail. The elements and thermostats also fail.
Obviously these issues affect both Direct HW and PV hot water though.
I don't see how you can claim your system is lower maintenance when much of the stuff is the same.
I have done very little maintenance on my Solar HW system and it has been running a long time.

Also about your economics, and as it may apply to other people. If you use your house as an example you should include some of  the cost of your solar system which seems to be huge. (?10kw)

Freezing and boiling are not issues for me either. I have a 20 or 30 tube system, i bought it long ago so I cant remember.

These all point to the fact that so much depends on specific circumstances, so you should do a proper analysis before you design or choose your system.
When designing, often the difference between say 85% and 95% solar power is not worth the extra up front cost if you have effective backup.
Also if you DIY then be aware of the regulatory issues and how it could possibly effect your insurance.
In Australia only electricians should be wiring systems above 120V DC.

Yes, HW tank issues issues affect Direct and PV hot water equally. However, you are quoting me out of context, for I was comparing my PV resistively-heated water with heat-pump hot water, and I think we would both agree that a stainless steel tank with $30 replaceable element will be a lot more reliable and long-lived than a heat pump. I surfed various forums to gauge people’s experience with heat pump reliability, and concluded that they are often an infinite problem source and money sink.

As to comparing complexity and reliability of Direct and PV hot water systems, they probably come in about the same, if you compare a Direct system with a mains voltage inverter/PV system that is dedicated entirely to producing hot water, but that will almost never be the case. In practice, the homeowner will already have or decide to have a grid-tied PV system, for all of the financial and environmental benefits that it provides in it’s own right. Then, the choice is between building a separate solar HW system, with collectors, pumps, plumbing, controller, backup etc, or adding a simple diverter module to send excess PV power to an electric storage tank. There simply is no argument about which is simpler and will be more reliable, and these days it is likely that the PV HW solution (added to a PV system that you have or plan to have anyway) will be cheaper as well. But if roof area is scarce, that could change everything.

I have been-there-done-that. When I first planned the PV system, I dutifully set aside an additional area of roof for my solar HW system. The fortunately I saw the light and realized that I would be bonkers to build two separate systems, and instead opted for a few more PV panels so that the PV system could do both. I have never looked back. My good mate with his 60 evacuated tubes would not go down that path if he had his time again. That system has cost him a small fortune, and all it can do is produce hot water, and it doesn’t even do that as well as my PV HW system. He is now a complete convert to PV diverted hot water, and is an engineer in an Australian company that is is building and selling PV diverters. I have no connection with the company BTW :) The writing is on the wall. Sales of direct solar HW systems have stagnated, while the popularity of PV HW is increasing. The times, they are a changin …

FYI, my PV system has a 6kW inverter, but about 10kW of panels, to compensate for severe shading in winter. The net result is that the performance in winter is about the same as an unshaded 6kW system. So it’s a respectable sized system, but certainly not huge. You can buy a 6kW system these days surprising cheaply and, as I have demonstrated, you can do a lot of useful things with that power – power your house, reverse-cycle heat and cool your house in the daytime, make hot water, and sell what is left over.
 

Offline Zeranin

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Re: Wanting to get into solar? Think HOT WATER
« Reply #92 on: July 07, 2016, 06:03:08 am »
I was thinking Zeranin that you should use your Hot water for Hydronic heating so you dont use the straight electric Heaters at night.
Just an idea.

Actualy a bad idea in my particular case. At night I use natural gas heating. My hot water production in winter using excess PV power just nicely matches my HW usage, with 2 adults in the house, so there is none left over for heating the house at night. It is much more efficient (x3 better) to use my excess PV power during the day to heat the house using reverse cycle, so that's what I do. It's true that I have excess PV power coming out of my ears in summer, even with the hot water production, which I use for cooling the house on very hot days, and the rest gets squirted out onto the grid so others may use it. I get paid handsomely for every kWh that the panels produce, so financially it makes no difference to me whether I use the PV power, or push it onto the grid, so it makes financial sense that I usefully use as much as possible to reduce my power and gas bills. Such ridiculously generous gross feed in tariff schemes are no longer available.
 

Offline HackedFridgeMagnet

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Re: Wanting to get into solar? Think HOT WATER
« Reply #93 on: July 07, 2016, 06:19:04 am »
This legislation is done on a state by state basis.

each state has a definition of what is 'electrical work'.

https://www.legislation.qld.gov.au/LEGISLTN/CURRENT/E/ElectricalSA02.pdf
from about page 24.  sorry its so long but I'm sure someone (lower case)  ;) would complain if I cut part of it out.
Quote
18
Meaning of
electrical work
(1)
Electrical work
 means—
(a)
connecting    electricity    s
upply    wiring    to    electrical
equipment  or  disconnecting 
electricity  supply  wiring
from electrical
 equipment; or
(b)
manufacturing,    constructing,    installing,    removing,
adding,    testing,    replacing,   
repairing,    altering    or
maintaining    electrical    equi
pment    or    an    electrical
installation.
Examples of electrical work—


installing low voltage electrical wiring in a building

installing   electrical   equipment   into   an   installation   coupler   or
interconnecter

replacing a low voltage electrical
 component of a washing machine


maintaining an electri
city entity’s overhead
 distribution system
(2)
Electrical work
 does not include the following—
[s 18]
Electrical Safety Act 2002
Part 1 Preliminary
Current as at 8 April 2016
Page 25
Authorised by the Parliamentary Counsel
(a)
work that involves connecti
ng electrical equipment to an
electricity  supply  by  means  of
  a  flexible  cord  plug  and
socket outlet;
(b)
work   on   a   non-electrical   
component   of   electrical
equipment,  if  the  person  carr
ying  out  the  work  is  not
exposed to an electrical hazard;
Examples for paragraph (b)—

painting electrical equipment covers

repairing hydraulic
components of an electrical motor

replacing a drive be
lt on a washing machine
(c)
replacing   electrical   equipment   or   a   component   of
electrical equipment if
 that task can be safely performed
by a person who does not have
expertise in carrying out
electrical work;
Examples for paragraph (c)—

replacing a fuse

replacing a light bulb in a light fitting
(d)
assembling,  making,  modify
ing  or  repairing  electrical
equipment  in  a  workplace  under  the 
Work  Health  and
Safety Act 2011
 that is prescribed under a regulation for
this  paragraph,  if  that  is 
the  principal  manufacturing
process at the workplace, and
arrangements are in place,
and are detailed in written form, for ensuring that—
(i)
the work is done safely and competently; and
(ii)    the equipment is tested to ensure compliance with
relevant standards;
(e)
building   or   repairi
ng   ducts,   conduits   or   troughs
(channels) where electrical wiri
ng will be or is installed,
if—
(i)
the channels are not intended to be earthed; and
(ii)    wiring  installed  in  the  channels  is  not  energised;
and
(iii)  the work is done under
the supervision of a person
licensed to perform electrical installation work;
[s 18]
Electrical Safety Act 2002
Part 1 Preliminary
Page 26
 Current as at 8 April 2016
Authorised by the Parliamentary Counsel
(f)
locating  or  mounting  elect
rical  equipment,  or  fixing
electrical   equipment   in   plac
e,   if   this   task   is   not
performed  in  relation  to  th
e  connection  of  electrical
equipment to an electricity supply;
(g)
assisting   a   licensed   electrical   worker   to   carry   out
electrical work, on
electrical equipmen
t under the direct
supervision  of  the  electrical
  worker,  if  the  assistance
does  not  involve  physical  co
ntact  with  any  energised
electrical equipment;
(h)
carrying   out   electrical   
work,   other   than   work   on
energised   electrical   equi
pment,   in   order   to   meet
eligibility   requirements   in
   relation   to   becoming   a
licensed  electrical  worker
  and  only  if  the  work  is
prescribed under a regulation for this paragraph;
(i)
building,  under  the  supervis
ion  of  an  elect
ricity  entity,
an  overhead  electric  line 
on  structures  that  do  not
already carry an energised overhead electric line;
(j)
laying,  cutting  or  sealing 
underground  cables  that  are
part of the works of an electri
city entity before the initial
connection of the cables to an electricity source;
(k)
recovering underground cables th
at are part of the works
of  an  electricity  entity 
after  disconnection  from  an
electricity source;
(l)
altering,    repairing,    main
taining    or    recovering    an
overhead  electric  line  that 
is  part  of  the  works  of  an
electricity  entity,  if  the  work  is  performed  under  the
entity's supervision and—
(i)
if  the  line  is  not  on 
supports  supporting  another
electric  line—the  line  h
as  been  isolated  from  an
electricity source so that
the closure of a switch can
not  energise  the  section  of  the  line  where  work  is
being done; or
(ii)    if the line is on supports
 supporting another electric
line—both   lines   have   been   isolated   from   an
electricity source so that
the closure of a switch can
not energise the section of
 the line where the work
[s 19]
Electrical Safety Act 2002
Part 1 Preliminary
Current as at 8 April 2016
Page 27
Authorised by the Parliamentary Counsel
is  being  done  or  an  adj
acent  section  of  the  other
line;
(m)   erecting    structures    for   
the    support    of    electrical
equipment;
Examples of structures—

electric poles and towers
(n)
locating,    mounting    or    fi
xing    in    place    electrical
equipment, other than—
(i)
making or terminating elec
trical connections to the
equipment; or
(ii)    installing  supply  conducto
rs  that  will  connect  the
equipment to a supply of electricity;
(o)
maintaining the structural pa
rts of the electrical traction
system  on  a  railway,  other  than  overhead  electric  lines,
that forms part of the works of
 an electrical entity, if the
work  is  structural  work 
performed  under  a  safe  system
of work.
19
Types of electrical work for this Act
(1)
Electrical installation work
 is electrical work associated with
an  electrical  installation,  but 
does  not  include  the  following
electrical work—
(a)
testing,  repairing  or  mainta
ining  electrical  equipment
included in the electrical installation;
(b)
electric   line   work   associ
ated   with   the   electrical
installation.
Examples of electrical installation work—

installing or altering wiring or fixed appliances in a building

installing or altering a switchboard
(2)
Electric  line  work
  is  electrical  work
  associated  with  an
electric line.
[s 20]
Electrical Safety Act 2002
Part 1 Preliminary
Page 28
 Current as at 8 April 2016
Authorised by the Parliamentary Counsel
Examples of el
ectric line work—

erecting  an  aerial  conductor  that
  is  part  of  the  works  of  an
electricity entity or of
an electrical installation

installing or maintaining street lighting circuits

testing   an   overhead   electrical   
line   to   ensure   it   is   correctly
connected
(3)
Electrical  equipment  work
  is  electrical  work  other  than
electrical installation work
or electric line work.
Examples of electrical equipment work—

repairing substation
electrical equipment

repairing an electric range, whether
or not it is part of an electrical
installation

installing, jointing or terminating covered cables

http://www.fairtrading.nsw.gov.au/ftw/Tradespeople/Home_building_licensing/Licence_classes_and_qualifications/Electrical.page

Tasmania
Quote
4. Meaning of "electrical work"

    (1) Electrical work is any one or more of the following:

        (a) work on the installation, repair, alteration or removal of an electrical circuit or associated fittings, equipment or accessories;

        (b) work on an electrical installation;

        (c) work on the installation, repair, alteration or removal of electrical infrastructure including lines and wires for the generation, transmission or distribution of electricity and also including supporting and protective structures relating to any such equipment, lines or wires;

        (d) work that has been determined by the Regulator, as defined in the Electricity Supply Industry Act 1995, to be regarded as specialist work.

    (2) Despite subregulation (1), electrical work does not include –

        (a) electrical work performed under an electrical safety management scheme approved under Part 8 of the Electricity Industry Safety and Administration Act 1997; or

        (b) any low voltage electrical work on telecommunications equipment that is carried out by technical workers trained in the telecommunications industry; or

        (c) any extra low voltage electrical work if the electrical work is not in a hazardous area as defined by AS 3000; or

        (d) the insertion of a plug into a socket outlet through which electricity is, or is to be, supplied in order to connect an electrical article or an extension cord to an electricity supply; or

        (e) repair work on an electrical article that is, or is to be, operated at a nominal electrical voltage of 250 volts or less with reference to earth and that electrical article, when manufactured, was to be connected to an electricity supply with a plug and cord; or

        (f) the affixing of a plug or socket to an extension cord through which electricity is, or is to be, supplied at a nominal electrical voltage of 250 volts or less with reference to earth.


The exceptions are important but I didn't see any that apply to this case.

Pretty sure you cant in QLD and TAS but not sure about NSW.

AFAIK (and I'm not a lawyer) my statements were correct on the regulations anyway.
ps. I dont agree with this level of restriction either.

 

Offline HackedFridgeMagnet

  • Super Contributor
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  • Posts: 1999
  • Country: au
Re: Wanting to get into solar? Think HOT WATER
« Reply #94 on: July 07, 2016, 06:27:22 am »
Planning on getting solar PV grid connect myself soon, but I will have to move/change the Evac tubes to fit it on.
 

Offline Someone

  • Super Contributor
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  • Posts: 3470
  • Country: au
    • send complaints here
Re: Wanting to get into solar? Think HOT WATER
« Reply #95 on: July 07, 2016, 09:48:56 am »
Pretty sure you cant in QLD and TAS but not sure about NSW.
NSW are unequivocal on the matter:
http://www.austlii.edu.au/au/legis/nsw/consol_act/esa2004309/s3.html
Does not include plug in appliances.

VIC only regulate the supply (sale) of certain electrical appliances:
http://www.austlii.edu.au/au/legis/vic/consol_act/esa1998209/s57.html
You are free to build your own if you do not sell it.

QLD:
http://www.austlii.edu.au/au/legis/qld/consol_act/esa2002169/s18.html
Cant do anything requiring skill without a license.

SA:
http://www.austlii.edu.au/au/legis/sa/consol_act/ea1996139/s4.html#electrical_installation
No worries

WA:
http://www.austlii.edu.au/au/legis/wa/consol_reg/er1991331/s4a.html'
Though there are exemptions, appliances are considered electrical work.

TAS:
http://www.austlii.edu.au/au/legis/tas/consol_reg/olwr2008472/
http://www.austlii.edu.au/au/legis/tas/consol_act/ola2005222/
A mess with inconsistent terminology, hard to determine if private DIY work is controlled.


So QLD and WA are restrictive, possibly TAS while the majority of Australia is sensible and allows anyone to make their own appliances. People from other countries think its ridiculous that we cant do the wiring or plumbing in our own houses, Australia is the exception rather than the norm. So the current roundup of Australian states is that two of them are prohibiting hobbyists (or even professionals) from making equipment powered by low voltage (mains).
 


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