[sudev]

The unit does come with a standby electric heater which can be used for such contingencies. That said, yesterday and today was smogy and cloudy day here. No problems as to heating. AFAIK even on cloudy days there is enough radiation to keep things hot. I saw this when we used solar cooker. Problem days are continuous rainy days. Lets us see how it goes through the winters as for the moment I have kept the plug pulled out on the standby heater.

[PatienceWins]

Is it possible to use solar water heater in apartments?

There is no roof top and I am wondering where and how to place the heater.

[sudev]

Originally Posted by PatienceWins

Is it possible to use solar water heater in apartments? There is no roof top and I am wondering where and how to place the heater.

Hmmm I think you need to discuss with manufacturers directly. There are units which use pumps etc. for flow purposes but then whole idea of energy saving becomes a bit diluted.

[ECM]

Few things must keep in mind if you are going to install a new solar heater in a new bunglow(flat appartment dont apply here as they are readily built).
Just with one point you can make a saving of around 40-50K,align your all bathrooms on a common wall for example eastern side of your bunglow,this saves a huge amount in pipelines,joints etc as all pipe lines from tank will be laid down only on the common side of wall..Please do NOT use pvc pipe if you are thinking of Solar heater,use deluxe quality metal pipes else in summer there will be a sure leakage in pvc pipes due to excess heat and moisture will come up on the walls and if this happens you will have to replast your expensive walls again+repaint all walls again.This had happened with one of my friend what he did is he did not replast his walls but stopped using solar,yes he repainted his home again and expense must be around 1 lac or more!

[aaggoswami]

Originally Posted by Mpower

Interesting! What happens on some cold winter days or rainy season where the sun dosent come out much. Back to the EB?

In Winters also, the hot water will come. Yes it will not be really hot as it will be in summer, but then it will be much hotter than warm water.
And on rainy days, till now we haven't faced much of a problem. Yes it wont work with full efficiency, but warm water will be available.

This is regarding our old system that we will be selling off now.
The new system with better circulation of heating liquid will be installed in two or three days. If possible, I will scan the brochure and keep it here.

@ECM :
Well the best thing to do is plan the piping accordingly in the planning phase and implement in construction phase. We had planned everything. All the three bathroom blocks have hot and cold water availability since the day we shifted in this house thanks to my father who planned it well.
About the pipes, well always metal pipes and if possible it must be insulated where ever it is open to elements. Here we can save a lot of energy as the temperature of the pipe wont vary much.

[Mpower]

Originally Posted by sudev

The unit does come with a standby electric heater which can be used for such contingencies. That said, yesterday and today was smogy and cloudy day here. No problems as to heating. AFAIK even on cloudy days there is enough radiation to keep things hot. I saw this when we used solar cooker. Problem days are continuous rainy days. Lets us see how it goes through the winters as for the moment I have kept the plug pulled out on the standby heater.

The standby heater is separate or is it integrated? I am looking for a system that will automatically pull electricity from the outlet on cold days to compensate for lack of solar. The heating coil can be the same.

I would like an intelligent system that will always provide me the same temp hot water while maximising solar and minimizing EB usage.

Frankly speaking ,its on the cold days that you really need hot water not the other way round.

[sudev]

@Mpower: The electric heater is integrated in to the hot water tank and is set to activate if the temperature fall below a certain present value. I have switched it off as I wanted to see how much pure solar heating would be able to cope.

[SumitB]

Some very interesting and useful information and a refreshing topic we have here. I will probably implement Solar Water heater in a new house I may be building in the near future. I did a google search and came up with this.

solar india solar power india solar home lighting solar power packs solar street lights garden lights solar powered street lights garden lights solar india tatabpsolar

solar india solar power india solar home lighting solar power packs solar street lights garden lights solar powered street lights garden lights solar india tatabpsolar

Anyone here has an experience with these products? The Hot Max looks really futuristic!

Also noticed that Govt. of Karnataka has made Solar Water heaters mandatory!
solar cookers solar lanterns solar cells cookers home lighting kits india solar cookers india lanterns solar cells india home lighting educational kits solar educational kits india

[Thad E Ginathom]

Our Venus water heater going strong here after about 18 months. There have been very, very few Chennai days with not enough sun to keep our 200Ltr model going, and for just one couple, that is plenty. We have not even fitted the electric heater that is supplied.

Good point about the insulation. We did not have that done. It is not too bad in the bathrooms, but it takes ages to run hot water at the kitchen sink --- and you know how, in Chennai, we hate to see water flow down the drain!

Our system is vacuum tube, but there is no heating fluid, but solid copper in the tube that acts as the heat pipe.

We have suffered one broken tube (good thing it is not the kind where the water flows in the tubes!), and have been waiting a couple of weeks for Venus to come and repair it.

[sudev]

Will have to dig in and find out what type of heating system out heater has. Perhaps some guru could list various systems and their strengths and weaknesses?

[sudev]

Running a solar water heater requires that you top up water in the heating circuit every fifteen day. Did that today at 0700hrs and was surprised to note heated water temperature at 82 degrees in the hot water storage tank!! That in spite of 10~11 degree centigrade temperature last night in Delhi.

[sudev]

This is question for long time users of solar water heaters.

Today, as mentioned earlier, while topping up fluid in the heat circuit I noticed that the "expansion" chamber is after the valve (see schematic). Since under normal operation both valve A & B are closed the whole purpose of expansion chamber is defeated. Should it not be as per the red alternate circuit on the left?



I have asked manufacturers advise too but would welcome comments.

[n_aditya]

Originally Posted by PatienceWins

Is it possible to use solar water heater in apartments?

There is no roof top and I am wondering where and how to place the heater.

Yes it is possible to use the solar water heater in apartments. The unit is placed on the terrace. We use Tata BP Solar. The initial investment is high but in the long run its all worth it. Plus we get some concession on our electricity bills as we are using a solar heater. Although the concession is not much, a penny saved, is a penny earned

Check this thread out : http://www.team-bhp.com/forum/shifti...r-sources.html

[sudev]

Okay a full winter has passed and I did calculation of savings. The electricity bill shows monthly savings of Rs900 plus monthly rebate of Rs200 from utility for installing solar heater. Monthly saving = Rs1100
Not bad return on investment on Rs50k. 2% return for six months or annualized to 1%. Plus I am saving energy.

The savings are even higher when I consider:
1. As compared to 4 hot water users last year this year there were 6 - younger son and daughter in law.
2. Last year we had two LPG water heaters working in addition to two electric gysers. This year one LPG heater (kitchen) and one gyser in younger sons bathroom (plumbing issues to be sorted during summers for better utilization next winter).
3. There were days when overcast sky meant that we switched on inbuilt standby electric heater to get hot water.

We got fairly hot to steaming water right through on tap right through. There were a few hiccup days when the heating was lower than expected. The cause is that the primary heat circuit has a blow arrangement to release pressure and this results in slow but steady reduction of liquid in this circuit. A regular top up with soft water - say every four/five days - was sufficient to address this.

[n_aditya]

Hey Sudev, its nice of you to post the savings you have earned through this kind of energy-saving investment.

This would give interested parties a valuable insight into the savings and ROI part.