# Interest group forums > Energy and Resource Conservation Forum >  Going Green only for the wealthy

## daveob

A few days ago, I was finishing off the refurbishment of a wooden window frame. It has, on and off, weather dependant for sanding, varnishing and glazing, taken about 6 weeks. Now I was figuring that after I complete the overhaul of the other 12 larger frames ( all cottage panes ) that I would have to start again with the first one. The light afternoon shower helped make up my mind that aluminium was the route to go. But I'm straying from the path here ...

During all this relaxing home-work time ( fabulous for clearing the head and having some contemplation time, btw ), I've been pondering ways to save some of our nearly R2k monthly utilities bill. It is high, but we have 2 adults ( full day working from home ), 2 kids, and an elderly tenant in the flat ( also home all day ).

So this got me thinking about 2 main options :

1. rainwater harvesting
2. solar geyser

so I whipped out the hose (garden hose, that is) and shoved some water down the gulleys that the gutter downpipes go into.

A side note to all : if you expecting a rainy season ahead, time to start clearing out the sand and leaves from the water drainage system.

Anyway, our property has a decent slope and it turns out that all the rainwater from the flat, garage, carport, and half the house all drain out through one large blue pipe into the garden just below the level of the pool.

Great, I thought. I can place a medium sized 1000 liter tank ( JoJo tank ) and catch all the water from the blue pipe. Add a few float switches and a 50 l/min pump, and pump any water in there back up to a 4,400 liter tank behind the carport - the highest point in the property. From here, there's a good 4 meter drop down to the house, so should be able to plumb this in to the toilet cistern and use it for filling the pool, all gravity feed.

Now if you are even thinking along these lines, there are 3 types of calculations you need to do :

1. how much water can I harvest, can I store it, how much will I save on my utilities bill.
2. how much will the system cost.
3. how long will it take to recover the cost.

The first section was really exciting, as I estimated a saving of around R 200 per month on the water and sewage disposal rates. Besides that, I really like the ideal of going green.

The "how much will it cost" needed a bit of homework at the local builders supply depot. Total bill for 2 tanks ( 1,000 and 4,400 l ), pump, switches, piping, connectors, cost for concrete slab and sundries, weighs in at a bit under R 9,000

Then came the interesting bit : the pay-back / recovery :

Assuming that I am going to fund this project from my bond, I would need to pay back R 9,000 @ 8,25% interest @ R 200 per month -- a total of 4,5 years.

Now if I add the solar system at around R15k  ( want to replace the 2 existing geysers with a 250 l model ), and my saving is R300 pm, that adds another 5 years repayment to the bond.

So I can "go green", but between the 2 projects, the saving of R 500 per month has to go straight back into the bond for the next 4,5 to 5 years.

Yes, I know water and power costs are on the increase so the savings will be greater in the long run, but is it worth it ? Is "going green" only an ideal for the wealthy ?

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AndyD (11-Sep-10), Dave A (10-Sep-10), Dave S (10-Sep-10)

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## murdock

i agree...one of the reasons i havent gone this route yet...it is way to expensive and takes too long to get any return worth talking about...dont forget the maintenace cost...and pump running cost...and dont let the water stand in the tanks for too long.

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## Dave S

> Is "going green" only an ideal for the wealthy ?


Put simply, yes, but this is only my opinion.

About 3-months ago my geyser burst so I said to myself... "Self, now is the perfect time to go 'green'". I got quotes for water reticulation (bath water, etc. stored for watering the garden), quotes for a solar geyser system, and rainwater capture system. The total bill would have been R117 900.00. The council would have given a small rebate on my electricity and my eletricity and water usage would drop by about 15 to 25%. An estimated total saving would have been approximately R750.00p/m, just above half the additional repayment on the bond would be.

From year 7 or 8 the new systems would start paying for themselves and I would start to see a saving, but after 8-years what would the condition of these system be? Now repairs and maintenance would start to become an issue and these would eat up my saving, in short, the systems will not be more affordable for me.

If one is building a new house and the "green" systems were installed at construction, it would then be affordable - long term, but not as an upgrade to existing property.

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## tec0

There is nothing green about going green it is just another overpriced industry. Look we need the technology so that we can run our households without the need of Eskom and all that but if you work out that you are actually paying MORE not less for your FREE power then you are right for thinking that âYES I am paying R50000 so that I can run my TV from natureâ how is that free?  :Confused:

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## daveob

Update :

three things I didn't factor into the original calculations that would have additional effects :

1. the rising cost of water / power would mean my saving would increase annually, making the bond repayment a bit quicker.

2. maintenance - this would quite probably wipe out the increase of savings in point '1' above.

3. insurance : would the insurance company that covers the bricks & mortar ( and existing geyser ) also cover the solar system, and at what additional premium ?

I'm tending to agree with Dave S and Murdock here - it is a wonderful ideal, but unless it was built and cost added to the original building price, the retro-fit just doesn't seem to make financial sense. 

But then again, if the systems were already in place when we made an offer for the property, we might just have placed a better offer ( closer to the asking price, by equal to the cost of the systems ), for the perk of having reduced utility accounts. So if we were willing to pay a bit extra at the time of purchase, why wouldn't we pay that bit extra now ?  This brings it down to a psycological (sp) thing. For example : buying for R1.1m "all in" and working, or paying R1.05m and spending an additional R50k to retro-fit.

Would I have paid 1.1m for this house ? - yes, without hesitation - because I wanted this house with this view. Any existing green systems would just have been a bonus.

I think the difference is that once we have bought, we've got the bond, the monthly re-payments are constant and we are loath to take cash out the bond and change our comfort zone.

I say that it's so much better for the environment, but ideals are only for the wealthy.  On the other side of the coin, maybe I got to start thinking a bit broader.

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AndyD (11-Sep-10)

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## BusFact

Very few of the "green" options make sense at the moment, financially speaking. They do afford you the following potential benefits, each of which will actually cost you:

- The feel good factor of doing something about environmental issues.
- The ability to not have to rely on a potentially increasingly erratic supply from your local municipality.
- The ability to remain calm when the municipality cuts off your water/power because they calim you owe them R10 billion and they will only discuss the possibility of a clerical error once you pay the bill.

Consider the extra costs as insurance and for peace of mind - not to save money .... yet.

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## murdock

the house i purchased a little while back was valued at 1.2...i put in an offer for 650 and we agreed on 700...so i thought why not take an additional bond for 200 to fix up and make the place look just the way we wanted it...

we did a couple calculation and decided to rather fix as we go and pay cash...the additional cost was just not worth it...some people say but a bond is the cheapest interest rate...correct but what about the 20 years you end having to pay off the amount...its like buying food on a budget credit card and paying it over 6 months...bad move unless you are absolutley desperate.

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## AndyD

> So this got me thinking about 2 main options :
> 1. rainwater harvesting
> 2. solar geyser


I think you're starting with the wrong projects. The problem with rain water storage is that you can't store enough to impact your municipal water bill in the dry seasons. Irrigation system uses about 30 litres per minute whilst a station is running so a ten thousand litre tank (which is about the max size you will want in your garden) will only run an irrigation system for about 5 1/2 hours. If your irrigation runs an hour each day then this is less than a weeks water.  




> ....quotes for a solar geyser system....... An estimated total saving would have been approximately R750.00p/m, just above half the additional repayment on the bond would be.


I agree this doesn't make financial sense.




> There is nothing green about going green it is just another overpriced industry.


There are many companies that have sprung up to make a quick buck on the green bandwagon but there are also realistic and financially viable things you can do to reduce your resource consumption.





> Very few of the "green" options make sense at the moment, financially speaking. They do afford you the following potential benefits, each of which will actually cost you:
> 
> - The feel good factor of doing something about environmental issues.
> - The ability to not have to rely on a potentially increasingly erratic supply from your local municipality.
> - The ability to remain calm when the municipality cuts off your water/power because they calim you owe them R10 billion and they will only discuss the possibility of a clerical error once you pay the bill.
> 
> Consider the extra costs as insurance and for peace of mind - not to save money .... yet.


This seems to be the general opinion. No offence meant but I'm not as surprised to hear this from a financial guy as I am from the engineering oriented members.

I'm going to be devils advocate on this one. I apologise for the long post in advance.

This is some of the energy efficiency improvements I’ve made at home along with the savings they’ve realised and the resultant payback times.



*1.	Replace low voltage halogen diachronic down-lights with pendant fittings which utilise CFL lamps.*

45 x 50watt downlights went in the bin and the transformers were sold on Gumtree for R700.00. 13 pendant fittings installed. The pendant fittings take 2 x 14watt CFL lamps each.

Cost;
13 Pendant fittings at R420.00 each = R5460.00
Installation was DIY but realistically for most people would be around R3000.00.

Savings;
My internal lighting was costing me 380 units per month (R266.00)
I reduced the lighting load from 2.25Kw to .364 Kw which is 16% of the original figure.
Savings in Rands = R223.00 per month.

Payback time;
R8460.00 / 223 = 37 months.

Just over 3 year payback (less with pending electricity price hikes) is a worthwhile exercise. This is also ignoring the R700.00 beer money from the Gumtree transformer sale.

________________________________

*2.	Replace external halogen flood lights with LED flood lights.*

4 x grotty looking 500watt halogen flood lights were replaced with nice LED floods.
The floodlights are on a day / night sensor and run for around 10 hours each night.

Cost.
4 x LED floodlights 	R3800.00
Installation		R1000.00

Savings
Running costs reduced from R434.00 per month to R21.00 per month

Payback Time
R4800.00 / 413 = less than 12 months.

________________________________

*3.	Install geyser blanket and insulate hot pipes where accessible and cold pipes for 2 meters.*


Cost.
1 x geyser blanket and 15 meters armourflex pipe insulation 	R500.00
Installation		R00.00 (do it yourself)

Savings
Reduced electric units consumed by HWC from 556 to 497. This equates to R41.30 saved each month 

Payback Time
R500.00 / 41.3 = less than 13 months.

________________________________

*4.	Install geyser timer clock switch.*

Timer installed and geyser turned of from 9pm-4am and 9am-4pm.

Cost.
1 x timer 7 day 16amp. Plus 1 x enclosure 150x200x150 	R400.00
Installation		R300.00

Savings
Reduced electric units consumed by HWC from 497 to 411. This equates to R60.20 saved each month 

Payback Time
R700.00 / 60.2 = less than 12 months.

________________________________

*5.	Pool and irrigation pump optimisation.*

When the pool was installed I was told that the pump must run for 6 hours each day lest the world as I know it will end. The irrigation had an 8 station set up running 30 mins each day per station. After much tweaking and twiddling I found that the pool will run for 2 hours each day with no detrimental effect or extra chemicals. The irrigation is on 5 mins per station in winter and 15 mins per station in summer and the garden is still very much alive and kicking..

Cost.
Nil

Savings
More electricity is saved in winter but taking the summer figures only the two .75kw pumps combined running time has reduced from 310 hours each month to 124. The electric cost has gone from R162.75 to R65.10.
It’s worth noting that if I was using council water for irrigation the saving in water and pro rata sewerage costs would also have been considerable. 

Payback Time
N/A (cost was nil)

________________________________

*6.	Roof insulation*

I included this in a recent house renovation. 40 mm isofoam (high impact polystyrene panels) and isotherm sheet (reflective silver membrane) 

The improvement in living standard is remarkable. It’s a pleasure to arrive home to a warm house in winter and a cool one in summer.

Cost.
190 sq meters Isofoam and isotherm 		R14000.00
Installation took Â½ a day			R1000.00

Savings
Difficult to quantify but the four air-con units and the three underfloor heating systems are now redundant. No air-con is needed even in the middle of summer and the only heating is three wall mounted panel heaters.
Best guess is we’re saving around R250.00 per month on heating or air-con power alone. We’re also saving the price of the equipment as well but if I work on power savings alone then R3000.00 per year.
.

Payback Time
R15000.00 / 3000 = 5 years.
I think this may be a little on the conservative side but even at 5 year payback time it’s money well spent. I can’t tell you how nice it is to be able to stroll around the house at night in winter clad in nothing but my jocks :-).

________________________________

Out of all the examples above, the only one which may warrant a bond extension is the roof insulation. Even at a five year payback it is a good investment. The interest you pay on the bond extension would be easily offset against predicted power price increases over the coming years so I’m not agreeing that the cost of credit would be a hindering factor.

I agree that after a point the outlay costs involved in realising further savings would become more and more prohibitive and payback times would become longer and longer the further down the green road you go. Maybe set up a system where you accumulate the savings your making in an account and use it to fund some energy saving exercises that wouldn't warrant a bond extension from a financial payback point of view.

 Every house is different so some of the suggestions may not be suitable for some premises but often if you look carefully at where you power is being consumed there will be alternative ways to reduce consumption.

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BusFact (11-Sep-10), Dave A (11-Sep-10), daveob (11-Sep-10), desA (20-Sep-10), SilverNodashi (19-Sep-10), wynn (13-Sep-10)

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## AndyD

As I mentioned in another thread I've reduced our electricity consumption by about 60% and to the point of being classed as a low consumption user and qualifying for free units each month.

There were other changes we've made which have also contributed. Many of these changes I don't have hard figure calculations for but the combined effect is considerable.

Replacement of 8 CRT PC monitors and 3 TV sets with LCD or LED equivalents. This has been ongoing over the last couple of years. All pc’s are also set to hibernate when inactive. 

Electric hob was due for replacement and we opted for LPG gas model.
This is kinda robbing Peter to pay Paul, I’m not sure if it’s a greener option but it is cheaper to run by about 30% and maybe more with the recent LPG pricing legislation. We opted to stay electric with the separate oven we purchased but the oven is only an occasional consumer.

I replaced all the hot water tap washers. A few of them had a tendency to dribble when the kids used them. They needed a firm hand to turn them off properly. New washers and the seats re-cut made them much lighter action.

The kids used to sleep with the landing light on all night, apparently it reduced the chance of the bogey man coming. I've managed to wean them off this habit. Other bad habits included running water whilst brushing teeth, using the hot tap in the kitchen when cold water was required, switching off lights and panel heaters when their use is unnecessary. We had a small education program and introduced a one Rand sin-tax when the kids (and adults) forgot things. The kids got an LED flashlight each (part of a deal for the landing light being off at night) and dog has been the proud beneficiary of new bedding from the proceeds but the deposits into the jar has now slowed to a trickle.

The tumble dryer has become persona non grata. I made a new undercover area for the washing line and cut the plug off the tumble dryer. We haven’t used it in a year and a half and it’s heading for the Gumtree classifieds.

When we renovated we went with a lower consumption shower head and lower volume flush toilets. I tested many models of both and would advise others to do the same. There are a lot of systems on the market which have sacrificed functionality for lower consumption; even some of the well known brand names were guilty of this. That said, the units we settled on have considerable reduced water usage. Our water+sewerage bill is way under R100.00 per month for a family of four. The reduction in hot water consumption also carries with it a corresponding reduction in electricity consumption.

Finally I toyed with a solar hybrid system for a couple of months but it turned out to be a very tricky retrofit on an existing hot water cylinder from an engineering and logistics point of view and it wasn’t giving the results I was looking for with the Cape Town winter climate.
I still have an ongoing project to make my retrofitted hot water system a heat pump / electric hybrid. The prototype is finished and it’s in full use. I now want to improve the control system and then rebuild the whole project from the ground up and make it a lot prettier now the problems are ironed out. I might even post it on one of my websites as a DIY project for others to try if I have time.  
This kind of project isn’t for everyone. Working with a very small budget meant all the equipment was second hand and generally makes for hard work. There was also a lot of welding, braising and complex electrical work required. Commercially built units are available but I don’t know the payback time on these and they don’t offer a retrofit option for an existing cylinder. I couldn’t bring myself the throw out my perfectly serviceable copper cylinder after the eighteen years faithful service it’s given us.

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wynn (13-Sep-10)

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## daveob

I just had a thought occur to me ( yep, I'm at home, and the lights just came on ), and after further consideration, it may just indicate that we're all barking up the wrong tree ( or maybe I just can't see the forest for the trees ) :

everyone seems to associate "going green" with saving money and focused on the pay-back period.

After looking at many options, ideas, the green band-wagon suppliers, etc, I am starting to thing that "Green" is a lifestyle choice related to saving the environment - it is not about saving a buck - it's all about caring for nature and giving the planet a chance ( now I'm starting to sound like a tree-hugger ).

So maybe going green really is only for the wealthy ( at least, definately not for the poor ).

Saving on the utilities cost is for everyone, but it's not automatically "green".

Be that as it may, I have to repair a pool this month, so next month I may just take the plunge and 'go green' with a rainwater catchment system (for topping up the pool, garden water and toilet cisterns), and a solar system to pre-heat water for the geyser. 

Yes, I understand that over time the cost is likely to be more than the alternative wasteful existing way things are done ( like using expensive drinking water to flush the loo ) and especially with the equipment life span, maintenance, etc, it stands only a small chance of saving on the utilities.

I'm not wealth, but I do care about our childrens future, and enough so that I would spend a bit to help make a difference.

Is this the right attitude ? Yes, well at least to me it is, so here goes a trip down the path least travelled ....

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Dave A (18-Sep-10)

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## adrianh

I think that one has to be careful with the whole "going green movement" I think that one has to consider sensible saving vs "Fasionable Greening". We changed our lights to CFL and LED long long ago. The motivation for doing so was simply to lower our expendiature on electricity. One could save water by catching rain water and also by using grey water. I think that you have to be practical. It is not practical for me to spend R8k to save a bit of electricity in the hope that the saving will be recovered in 5 years.

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AndyD (17-Sep-10)

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## adrianh

Now if you wanna talk about savings then look at cars. My one car is ultra green and the other somewhat green.

I drive a 1100 UNO. The car serves as a bus, lorry, tractor, garbage truck and even a tow truck. It uses practically no petrol, goes like a bomb and costs very little to maintain. It doesn't even have a radio, so I save on radio waves (ok, it got stolen in my driveway - The buggers climbed under the car and cut the battery cable). The other car is a 1.6 Opel Corsa - fuel consumption is good. (Ok, I just spent R2K on the clutch)

We are quick to look at spending R8K to save 50c a month on electricity while we drive a 4X4 5.6L V8...

Hey AndyD, what car do you drive?

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## AndyD

> everyone seems to associate "going green" with saving money and focused on the pay-back period.
> 
> After looking at many options, ideas, the green band-wagon suppliers, etc, I am starting to thing that "Green" is a lifestyle choice related to saving the environment - it is not about saving a buck - it's all about caring for nature and giving the planet a chance ( now I'm starting to sound like a tree-hugger ).


Oooh you went a little fuzzy there for a minute Daveob but I think you're back now :Big Grin:  
For me it's about being economical with resources and not being lavish and wasteful. I do have concerns about the environment but I'm not a raving 'Greeny' by any means. The saving money deal comes hand in hand with efficient resource utilization.
With my particular efforts, I find it's just easier to set goals and measure the effectiveness of eco-friendly improvements by looking at how much they save on the bills. With electrical consumption the energy savings, carbon footprint savings, CO2/greenhouse gas emissions savings and the money savings are pretty much proportional. I suppose the other way would be to use one of those online carbon footprint tools but I don't have the time or patience to go that route. 




> So maybe going green really is only for the wealthy ( at least, definately not for the poor ).


I think it depends what level and your definition of going green. The poor would benefit from turning off unnecessary lights or using CFL lamps instead of filament or halogen. They may also benefit from installing a geyser blanket or not overfilling the kettle when they use it. I agree that some higher outlay systems would only make sense for the wealthy.




> Saving on the utilities cost is for everyone, but it's not automatically "green".


I think this is another one that depends on the 'Green' definition but I understand what you're saying.  




> I'm not wealth, but I do care about our childrens future, and enough so that I would spend a bit to help make a difference.
> 
> Is this the right attitude ? Yes, well at least to me it is, so here goes a trip down the path least travelled ....


It sounds like we're in a similar position, I would be interested to hear how your solar heating pans out.




> I think that one has to be careful with the whole "going green movement" I think that one has to consider sensible saving vs "Fasionable Greening". We changed our lights to CFL and LED long long ago. The motivation for doing so was simply to lower our expendiature on electricity. One could save water by catching rain water and also by using grey water. I think that you have to be practical. It is not practical for me to spend R8k to save a bit of electricity in the hope that the saving will be recovered in 5 years.


This sounds like a pragmatic approach but there's many people around who haven't even taken the basic, practical steps which don't involve capital outlay and save money from day one.
I know three friends who were convinced to put in gray water and rain water systems during the drought period in Cape Town a few years ago and all three systems turned out to be a white elephant. All three of them dumped the systems after less than a year and after spending thousands of Rands installing them.




> Now if you wanna talk about savings then look at cars. My one car is ultra green and the other somewhat green.
> 
> I drive a 1100 UNO. The car serves as a bus, lorry, tractor, garbage truck and even a tow truck. It uses practically no petrol, goes like a bomb and costs very little to maintain. It doesn't even have a radio, so I save on radio waves (ok, it got stolen in my driveway - The buggers climbed under the car and cut the battery cable). The other car is a 1.6 Opel Corsa - fuel consumption is good. (Ok, I just spent R2K on the clutch)
> 
> We are quick to look at spending R8K to save 50c a month on electricity while we drive a 4X4 5.6L V8...
> 
> Hey AndyD, what car do you drive?


Lol, I nearly shed a tear for your poor Uno, sounds like it takes a beating.
I drive a newish 1.6 Nissan Livina (petrol) as a work vehicle and a 3 year old Renault Scenic Diesel for a family car. Wifey drives an oldish 1.3 Corolla for a runaround and also the Scenic. All my other company vehicles are 1.4i Corsa bakkies. I don't think we're going to get any green awards for our car choices but the Renault is particularly economical, (consistently less than 5.5l/100km) even with the air-con running. They're all practical vehicles, we do average mileage, we're not particularly shy about using the air-con ......or the radios:-)

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daveob (17-Sep-10)

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## daveob

> I think it depends what level and your definition of going green. The poor would benefit from turning off unnecessary lights or using CFL lamps instead of filament or halogen. They may also benefit from installing a geyser blanket or not overfilling the kettle when they use it. I agree that some higher outlay systems would only make sense for the wealthy.


I know a few "not so well off" people ( including our once a week domestic helper ), and none of them even have a geyser. To wash with warm water they have to boil the kettle. So that got me thinking about doing some research on a small project that can be afforded reasonably easily by the 'employer' and which would make a huge difference to the lives of the family you decide to help :

I would like to source a reasonably priced container that can :
1. be used to store hot water from a copper / plastic tubing solar panel circulated via thermosyphon (sp?)
2. can be easily insulated to help retain some heat.

The initial thinking is to erect a small gum pole tower with the solar panel and tank mounted, so it is gravity feed. A toilet cistern style inlet valve would keep it topped up, and it would have a tap fitting to draw hot water from the tank. This could then be adapted to add a shower.

There would be no element. The thinking is not to create hot water 24 hours a day - rather to have a tank ( say, 50 or 75 liters ) of warm / hot water available when they return home from work each day.

I believe it could be put together reasonably inexpensive and would create huge benefit for an entire family.

Any input / ideas / pointer that anyone could provide would be greatly appreciated.

Sorry, but I'm in tree-hugger mode today.

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AndyD (17-Sep-10)

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## daveob

> efficient resource utilization


Note to Dave_A : there's a potential caption for the new forum you wanted to add.

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Dave A (18-Sep-10)

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## adrianh

There is a truth in "Going green is for the rich" The rest of us simply save what we can because we have very limited resources to start with.

The Green club is very similar to diets. People go on the latest fad diet in the hope that it would make them thin without going to too much trouble. Spend R10K on a machine, swallow a pill, but don't exert yourself too much. We want to diet and get fit by not inconveniencing ourselves. People want to be seen driving a Prius.

There are ways to save lots of money and save resources but with it comes inconvenience - Take a bus, train create a lift club - you buy the lawnmower and your neighbour buys the weed eater and you share - use one anothers skill and barter rather than spending money - grow food etc...

*We are quick to save money by spending money without inconveniece,mut we are not so quick to make real hard differences - and yes I also speak for myself!*

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## AndyD

> I would like to source a reasonably priced container that can :
> 1. be used to store hot water from a copper / plastic tubing solar panel circulated via thermosyphon (sp?)
> 2. can be easily insulated to help retain some heat.
> 
> The initial thinking is to erect a small gum pole tower with the solar panel and tank mounted, so it is gravity feed. A toilet cistern style inlet valve would keep it topped up, and it would have a tap fitting to draw hot water from the tank. This could then be adapted to add a shower.
> 
> There would be no element. The thinking is not to create hot water 24 hours a day - rather to have a tank ( say, 50 or 75 liters ) of warm / hot water available when they return home from work each day.


There's no reason you can't do this with a slightly larger tank (c.150 litres) and if you go to town on the insulation you could still have hot water in the morning as well.

For insulation I would consider cladding the tank in high impact polystyrene isoboard panels, same as I used in my roof, they can be easily cut and shaped to fit. Armourflex all the pipework as well. You would need to make sure it's all closed cell insulation and not hygroscopic to prevent it becoming sodden in rain otherwise it will require painting or similar. Wet insulation is useless. I'm guessing you would need 100mm thick insulation and the pipework design would need to prevent water circulation or back siphoning during non-sunny times so all the heat won't be lost through the solar panel basically working in reverse.

I think anything copper in this application will be like a flashing neon saying 'steal me'. For a solar panel maybe consider one of those flexible swimming pool types that you can roll out on your roof. I only got close to one once but I think it was made from low density polyethylene which should make it cheap and fairly hardy. You could maybe hang it like a curtain around the pole or from a frame. It would certainly be better than a flat glass covered panel in windy conditions like Cape Town.

I'm already excited. There's no rush, just post on Monday with details on how your prototype performs:-)

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daveob (18-Sep-10)

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## AndyD

> There are ways to save lots of money and save resources but with it comes inconvenience - Take a bus, train create a lift club - you buy the lawnmower and your neighbour buys the weed eater and you share - use one anothers skill and barter rather than spending money - grow food etc...
> 
> *We are quick to save money by spending money without inconveniece,mut we are not so quick to make real hard differences - and yes I also speak for myself!*


This is a valid point, but I see this kind of lifestyle as the next step and one I'm not sure I'm ready to take. I can make further improvements to my impact on the planet without foregoing the way of life which I'm accustomed to.  
What you're suggesting is a complete change in lifestyle and even culture. Maybe my childrens children will commute on communal or public transport, not travel for pleasure, live in a small dwelling without extravagances, braai in a microwave and make the 'real hard differences' out of what might be absolute necessity by that time. Hopefully for them they won't miss what they never had....I for one plan to tan a few chops the old fashioned way tomorrow and to hell with the emissions.

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## daveob

> There's no reason you can't do this with a slightly larger tank (c.150 litres)


Thanks, and I agree with you on this. I just want to do the experimental project on a slightly smaller scale first.




> the pipework design would need to prevent water circulation or back siphoning during non-sunny times so all the heat won't be lost through the solar panel basically working in reverse.


OK. My understanding on the theory is that the water tank sits higher than the panels, and the feed goes from the bottom of the tank to the bottom of the panel, and from the top of the panel back to the tank ( I don't think the re-entry position is as important as the cooler water feed from the tank to panel, as long as they not right next to each other ). The Thermosiphon effect will allow the cooler water to flow from the bottom of the tank to the bottom of the panel, and as it warms, it rises and returns to the tank. When there is no sunlight / UV warming the solar panel, the water in the panel does not rise, and the coldest water in the entire cycle will drop to the lowest point, in this case the solar panel, where it will remain until such time as it again gets warmed to a temperature higher than the coldest water in the tank, and the circulation current starts up again. So during this 'no warming' time, there should not be any circulation, and the warm water would remain at the highest point, in the tank.




> I think anything copper in this application will be like a flashing neon saying 'steal me'.


Agreed. I am planning a trip to a few stores to look at the temperature range on some tubing, as well as the connectors available for joining them.

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AndyD (20-Sep-10)

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## SilverNodashi

@daveob, 

What kind of panels would you use, and what type of storage take do you have in mind? I'm interested in a similar setup and would like to keep the costs to a minimum as well.

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## daveob

> @daveob, 
> 
> What kind of panels would you use, and what type of storage take do you have in mind? I'm interested in a similar setup and would like to keep the costs to a minimum as well.


Hi Rudi

For the system to be donated to a less fortunate individual, I think that as much of the material as possible should have little resale / scrap value. For this reason, I would be looking at various plastic drums and pipes that could withstand the higher temperatures. I think that as long as the insulation is effective, there shouldn't be any pros / cons between the metal and plastic units.

For my home system, I am thinking of using a standard pressure geyser about 200 / 250 liters and a number of home made panels using copper tubing. The geyser will be in the garage on a robust stand ( 3 m from the house ) and the solar panels either side of a east / west facing wall which gets sun literally from sunrise to about 1 hour before sunset. 

My logic is that as we are at home all day, the east facing panels will capture plenty of heat for the daily washing, dishes, etc. The west facing then would top-up the heat for the later afternoon and evening baths / shower / dishes. The length of the wall is about 8 meters, so I have plenty of space to add additional panels. Also, if I can insulate the geyser sufficiently to keep some heat overnight, it may well be worth it to add a second geyser ( and possibly more panels ) to be used in the winter months so that I can do away with the eskom powered geyser completely.

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## AndyD

> @daveob, 
> 
> ....what type of storage take do you have in mind?


For a small scale system I'm thinking you can use a storage bin with a clip on lid. I think they're about 70 litres and they sell them at Pick&Pay, Makro etc they're not expensive.

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## AndyD

I was thinking about this type of flexible panel;

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## daveob

> I was thinking about this type of flexible panel;


Hi Andy

Do you know if that is available locally ? 

Where did you get the pic from ?

Would be a lot easier than a load of T connectors on black plastic piping.

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## SilverNodashi

> Hi Rudi
> 
> For the system to be donated to a less fortunate individual, I think that as much of the material as possible should have little resale / scrap value. For this reason, I would be looking at various plastic drums and pipes that could withstand the higher temperatures. I think that as long as the insulation is effective, there shouldn't be any pros / cons between the metal and plastic units.






> For my home system, I am thinking of using a standard pressure geyser about 200 / 250 liters and a number of home made panels using copper tubing. The geyser will be in the garage on a robust stand ( 3 m from the house ) and the solar panels either side of a east / west facing wall which gets sun literally from sunrise to about 1 hour before sunset.


Are you going to buy a new geyser, or re-use an existing one?

Just some thoughts:

- since you're using a standard geyser it might be easier to use the one already installed (the plumbing already works well), but have the inlet run through the copper pipes on the roof first, then into the geyser? The roof should also help to keep in more heat and a geyser blanket would help as well. 
-  thicker copper pipes will probably work better, but pipes made of thicker tubing (i.e. the sides, I don't know what you call this) would keep the water warmer for longer since the heat is in the pipes. 

But, would lead pipes, or even black corrugation (some can withstand high pressure, but a pressure release valve might be needed)  be as effective? 




> My logic is that as we are at home all day, the east facing panels will capture plenty of heat for the daily washing, dishes, etc. The west facing then would top-up the heat for the later afternoon and evening baths / shower / dishes. The length of the wall is about 8 meters, so I have plenty of space to add additional panels. Also, if I can insulate the geyser sufficiently to keep some heat overnight, it may well be worth it to add a second geyser ( and possibly more panels ) to be used in the winter months so that I can do away with the eskom powered geyser completely.


sounds good, please update us once it's done. 

Wouldn't North facing be better all-day round?

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## daveob

> - since you're using a standard geyser it might be easier to use the one already installed (the plumbing already works well), but have the inlet run through the copper pipes on the roof first, then into the geyser?
> 
> Wouldn't North facing be better all-day round?


Problem I have is that the north facing side of the roof is mostly in the shade due to trees and the neighbours house.

Also, to use the existing geyser I would have to add a pump as the ideal location for the panels next to the garage is higher than the existing geyser, so the thermosiphon effect would not work.

Will do some research about the cost of a new 250 liter geyser. I know most are made by Kwikot, but I would (hopefully) end up throwing the element away. Does anyone know of other high pressure tank manufacturers, pref in the Durban area ?

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## AndyD

> Hi Andy
> 
> Do you know if that is available locally ? 
> 
> Where did you get the pic from ?
> 
> Would be a lot easier than a load of T connectors on black plastic piping.


I think most of the pool heating companies have their own version of the flexible panels.

http://www.setsolar.co.za/solarheating.htm

And 
http://www.vottle.com/home-and-garde...-sale_v1567543

Were the web locations of those particular photos.

Most pool solar panels are only rated to around 1 bar pressure so you can't use them on a standard pressure geyser system.

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## desA

If anyone is seriously interested in thermal storage technologies - drop me a PM.

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## wynn

Ooh! now you guys are sounding all 'new agey' next you will be saying cob earth walls and sod roofs.

I believe that all savings on electricity and water is 'green' even if the idea is to save money first, yes, I worry about the repayment period of the investment.

Any water saved is a good thing.

I have just set up a grey water garden watering system for about R150.00

It will only work if your shower outlet is above the level of your garden.

I bought a 'Lay Flat hose 100mmx10M from the hardware store and attached it to my shower outlet, on the other end I installed a 110x50MM eccentric Marley s&v waste pvc reducer, with a Marley 40x1 1/4" female bsp waste s&v pvc adaptor siliconed into the 50mm outlet, ptfe'd and screwed in a 32x20mm threaded galv bush and a 20mm male gardena hose adaptor to which I attached the garden hose and 'voila'

When the wife or I shower the LFpipe fills up, acts as a holding bladder, then gently trickles water into the chosen flower bed.

TIPS:-  you may have to cut a tiny air hole into the LF pipe just above the shower inlet to prevent the system creating a vacuum and so that it can drain easily, insert the reducer well into the LFpipe use cable ties to attach, make sure that the reducer is set at the lowest point of the pipe so that it can drain completely, move the LFpipe and hose around the garden and lawn regularly, don't take long showers.   :Cool:

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## murdock

my nieghbour got smart and invested in some irrigation piping which he detoured from his pool pump...up the wall onto his roof made a couple of loops and back down to the pool pump...now he always has a warm pool to swim in...whenever the pool pump runs it circulates the water over the roof and back into the pool.

just the cost of the piping and he did it himself...it been working for about 3 years already.

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AndyD (20-Sep-10)

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## murdock

i might be speaking out of line here but...where i live the heat in the roof is so hot that putting a geyser blanket is a crazy idea...when it gets hot the heat from the geyser aint going anywhere other than hotter...so it might hold the heat at night but during the day it would keep the heat out...not such a smart idea because now your element has to do all work to heat up the water.

something else i noted when stripping a geyser that the kwikhot geyser already has thermal insulation around it...between the tank and the outer casing...anyone checked this before they spent money buying a geyser blanket?
if you are gona all the trouble of fitting a geyser blanket do you lag your pipes because the loss waitng for the cold water to run out the pipes must be a waste.

this reminds me of old army days...water on...water off...wash...water on cheers next.

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## SilverNodashi

> Ooh! now you guys are sounding all 'new agey' next you will be saying cob earth walls and sod roofs.
> 
> I believe that all savings on electricity and water is 'green' even if the idea is to save money first, yes, I worry about the repayment period of the investment.
> 
> Any water saved is a good thing.
> 
> I have just set up a grey water garden watering system for about R150.00
> 
> It will only work if your shower outlet is above the level of your garden.
> ...


sounds like a great idea and probably very effective as well. Care to put some pics of your setup on the web? Someone else might learn a lot from it  :Smile: 




> my nieghbour got smart and invested in some irrigation piping which he detoured from his pool pump...up the wall onto his roof made a couple of loops and back down to the pool pump...now he always has a warm pool to swim in...whenever the pool pump runs it circulates the water over the roof and back into the pool.
> 
> just the cost of the piping and he did it himself...it been working for about 3 years already.


I thought of doing something similar to this setup, but with a small twist. Instead of running the pipes directly back to the pool, have the water run out on the roof and cool off the roof, then let the gutters run back to the pool. This way you get a nice cool roof, which cuts down on electricity (i.e. less Aircon use) and a warmer pool. If you want to save a few extra bux, then use a solar powered pool pump which could run 12-16 hours a day.

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AndyD (20-Sep-10)

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## Dave A

> This way you get a nice cool roof, which cuts down on electricity (i.e. less Aircon use) and a warmer pool.


I see two possible downsides to this - higher water consumption and a higher electricity bill.

You're going to lose a fair amount of water to evaporation - which will also help with cooling the roof, of course, but might not help much on the warm swimming pool front.

The other benefit of a closed system is it shouldn't load the pump as much as the "open system" - the closed system of return piping should help offset the head pressure.

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## AndyD

> thought of doing something similar to this setup, but with a small twist. Instead of running the pipes directly back to the pool, have the water run out on the roof and cool off the roof, then let the gutters run back to the pool.


It's a nice idea but if you have a salt pool then corrosion would be a problem especially with a corrugated roof but also with the fasteners and clips on other roofs. Also it might play havoc with the chlorine levels as well as extra organic debris from the roof and gutters ending up int the pool.

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## wynn

Here is a pic of my grey water system, hope they are clear enough!

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## wynn

And the other end!

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## murdock

if you want to cool the roof space down what about fitting a solar powered fan...one thing to remember an extractor fan will draw air from the closest  point...so when you want to put a fan in a lrge area like under the house or in the roof it is better to suck air from the outside and pressurise the space...once it has filled the space with air it wil lthen release the air out of the gaps in the roof.

the other way to insulate the roof is with that white board which can be fitted instead of ceiling boards...this stuff works well...the only problem is you cannot fit lights like downlights they tend to get hot then drop out the roof.

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## AndyD

> iit is better to suck air from the outside and pressurise the space...once it has filled the space with air it wil lthen release the air out of the gaps in the roof.


If you pressurise the roof space especially in an older building you could find the house gets very dusty or even worse you might get allergies from the think pink insulation. The higher pressure in the roof will cause airflow through any gaps in the cornice or lighting fitting holes in the ceiling into the rooms of the house.

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