[hellmet]

Has anyone on this forum successfully moved off the electric grid totally or partially? I'm thoroughly interested in being able to live off the grid and I've dreams of building such a home in the future (including other self-sustenance ideas), but what is it I can do now and how so I'm atleast partially self-reliant for energy?

I'm currently interested in a grid-connected system for my apartment where alternate sources of power from either solar or wind are fed to a energy-collector from which the house draws its energy. Fluctuations of energy due to sun vanishing or wind diminishing are hence compensated by drawing more power from the grid. The advantage of this being that the end-user does not need to install batteries and doesn't have to bother about overdrawing power from the alternate-energy setup (AC/fridge), while the flip side is s/he would have to totally depend on the grid when the alternate-energy setup isn't generating anything (lack of sun/ night for solar, or lack of sufficient wind for turbines).

Giving the current location of my apartment (bang in the city) wind energy is ruled out, however my city receives plenty of sunshine so I'd like to invest in a solar powered setup. Ideally I'd like to run every device (except the ACs) on solar energy but costs could probably get prohibitive.

Is there anyone here on the forum that can shed more light on their (or other) experiences with solar energy setup and the costs and caveats involved?

Thanks for reading!

[.anshuman]

A few hours in any rural area should give you an idea on living without power supply. Haryana as an example is a state with electricity extended to even the remotest places, but the number of hours these places get electricity is really very limited, with most farm connections getting as low as 3-5 hours a day. So how do people especially the affluent ones manage? People i know use- Generators for pumping water and other critical work for short durations, Inverters for low consumption appliances and some are shifting to solar usage for heating water etc in winters. I am not really sure if all of household usage can be sourced by solar energy. There is a good amount of Government subsidy on buying solar energy devices.

[hellmet]

Thanks .anshuman.

I'm hoping to run these devices:
2 refrigerators
1 microwave (used very lightly)
one PC | one TV (used alternately)
one grinder
6 (CFL) lights and three fans at maximum usage. Generally NO lights & 2 fans during daytime.

At worst case I'd like to draw enough energy from the solar system to run the PC|TV and lighting+fans during full daylight, everything else could run on government energy.
That would be:
PC | 29" TV =~ <400W
6x20W CFLs =120W
3x75W Fans = 225W (assuming fan running at speed 5, which is never)
Total Wattage = 745W

So assuming my calculations are right, I need a 0.5MW system at the minimum and a 1MW system for better results. How expensive would that be? This would anyways, be a grid-connected system so it shouldn't matter much if I run low on solar-power, it would be compensated by government provided power.

[SirAlec]

One of my client is a German Engineer who is on work visa for BK World renewal trust. He has been interviewed by BBC. His design is outstanding. A whole 25 acre of are is powered by Solar. The whole kitchen runs on solar power. The parabolic sunlight catcher moves according to sunlight during the day.

I have a similar plan for a land that have acquired for a farm house recently. He says for a typical house with a load of 5 KVA max will cost about 29 lacs. and yeah whole equipment comes from Germany.

[hellmet]

^ That is nice, but not the price He's used a 'sunlight tracking' solar system which was designed based on sunflower's ability to track the sun.

I'd like to correct my previous post. I think I should have said "1KW" and not "MW". Anyway I'm terrible at electrical/tronics so please pardon me.

[splitsecond]

Yea me too once thought of 2KWsolar energy, But cost of panels put me off, the price of inverter and battery are ok, the deal breaker is the solar panels, they cost around 6000Rs for 50W with 25yr warranty. So 1000W requires panels costing 1.2lakhs. ( now central govt is giving 30% subsidy for home solar inverters, not sure)

In western countries homes with grid tied solar inverters have two meters, the second one records the extra energy generated by ones solar panels, which is given back to the grid, In such a system the energy bill to be paid will be nil. I asked about this system at electricity office, but they said its not possible here.

Originally Posted by hellmet

So assuming my calculations are right, I need a 0.5MW system at the minimum and a 1MW system for better results. How expensive would that be? This would anyways, be a grid-connected system so it shouldn't matter much if I run low on solar-power, it would be compensated by government provided power.

1kw inverter - Rs 10000
150ah battery - 13000
1000w panels - 1.2 lakhs

[cranky]

SO I was converting my day use to solar (no batteries, just a series-connected grid).

It was impossible. The panels would run a couple lakhs on their own.

For a battery/inverter system the cost was about half that, and provide around 500 watts of power (which for daytime use is sufficient).

Would not advise running high-current appliances through a battery/inverter system, the weak link is usually the inverter. Refrigerators and TVs can draw huge startup current. Not sure off-grid will work for that stuff.

PC/laptops, fans, lights etc work fine on alternative energy. Going fully off grid is possible if you never need anything more than this. I suspect in Hyd you will need airconditioners etc. Not feasible off-grid, unless using a large generator of some sort.

The requirements you have listed do not seem to be taxing. A kilowatt of power should be doable. Don't forget you can cook/warm water using sunlight as well, not just generate electricity. I am aware climatic challenges exist in that part of the country, but one can still be slightly creative.

[vishwaschettri]

Hi Hellmet,

My 2 cents on the alternative energy.

Internationally zero energy building concept is not a new thing but in India it is still a distant dream. The main roadblock being the feeding into grid system not being available.

Let say you go ahead and install all the solar-panels you need for your peak demand (Which are not very expensive now compared to say the price 5 years back) but what do you do during the night? You will need to invest in huge batteries and AC to DC to AC inverters thus driving up the capital costs and operational costs.
A simple solution would have been to be able to feed the excess power during the day back to the grid where it gets utilized at places which have peak demand during the day (offices / industries) and you draw it back during the night. Unfortunately this is not possible in India yet for any project less that 100 KW atleast and ofcourse you will have to deal with lots of red tapism.

Without this your best bet is to be on the solar energy during the day and on the grid during night.

Solar panels today make ecological sense with the payback period being approx. 8yrs (It was 35yrs for a project in Delhi done by TERI 10-15 yrs back with the life of PV being 25 yrs. So basically no payback).
The day it comes down to 5 yrs they will start making economic sense as well. This will get driven more by increasing power tariff than lowering panel cost IMHO. Internationally power cost 16-18 rs/unit and that is where it will be in India once subsidies are pulled back.

So lets say Solar panel for 1 KW - 1.2 lakhs (Based on Splitsecond. You can check with moserbaer & TATA BP who are big players in this business). You will definitely get some subsidy on initial purchase as well as monthly electricity bill, but lets not consider them for now. So 1 KW costs you 1.2 Lakh.

This is 8 hrs of 1 KW daily for next 25 yrs i.e 8 units daily. Now tariff up north is around 6 rs/unit. Some simple maths

120000/(8*6) = 2500 days i.e 6.8 yrs payback

Some things I have not considered in above calculations
1. The power tariffs will definitely increase in future thus bringing down the payback time considerably.
2. You will not be able to consume @ 1 unit/Hr for those 8 hrs of sunlight. Thus increasing the payback time unless you store it in battery or sell it to your neighbours.
3. The feeling that you are doing something to save the earth. Priceless.

The road will be tough but I'll urge you to go ahead and take the leap.

Cheers
Vishwas

P.S.
You can also explore mini bio gas plan being run on the kitchen waste and sewage (which are extensively and successfully being used in villages) which can power a small gen-set for the night use. A LPG genset readily available in the market can be adapted for biogas application.

[splitsecond]

Here is an ebay link for 2kw inverter system connected to 1kw panels, cost 1.5lakhs, the seller also explains feasibility of solar powered homes in India, good read.
http://www.ebay.in/itm/1-KW-SOLAR-PO...item2555abe7db

Originally Posted by vishwaschettri

Internationally zero energy building concept is not a new thing but in India it is still a distant dream. The main roadblock being the feeding into grid system not being available.

Let say you go ahead and install all the solar-panels you need for your peak demand (Which are not very expensive now compared to say the price 5 years back) but what do you do during the night? You will need to invest in huge batteries and AC to DC to AC inverters thus driving up the capital costs and operational costs.
A simple solution would have been to be able to feed the excess power during the day back to the grid where it gets utilized at places which have peak demand during the day (offices / industries) and you draw it back during the night. Unfortunately this is not possible in India yet for any project less that 100 KW atleast and ofcourse you will have to deal with lots of red tapism.

Yea, i was really hoping for this system here. Any state in india which supports this?

[hellmet]

Thank you 'splitsecond' 'cranky' and 'vishwaschettri' for putting forward practicalities of going solar. The ebay link is funny and yet very informative too! Thanks.

From that link, it looks like I'd need 10sq mts for just one 1KW which might be too much too ask given that I share the terrace with fellow residents of the apartment complex.

This part of the country doesn't need to rely too much on hot water as it barely gets anywhere as cold as Delhi or the likes in the winter. Cooking is another high energy use that could be moved to solar devices but again isn't feasible living in an apartment as we'd have to climb 4 flights of stairs to get to the terrace.

Not sure what to do in such a situation. It is such a shame the government isn't doing anything much at the ground level to boost renewable energy use.

[Abes]

Excellent idea, a bit expensive though!!
Solar inverters are available in india, at least that is what i see on the net. See one such website.
Solar water heaters are very popular now-a-days!
& Solar powered (partly = hybrid) AC's of 1T & 1.5T capacities are available!

[hellmet]

Thanks Abes for the link. This reminds me of my trip to Kerala where I saw outlets for Tata BP Solar in/around Trivandrum, though I did not have a chance to stop and visit them. Does anyone know if Tata BP Solar | Mosebaer have outlets in Hyderabad? I'd love to go see what they have on offer! I hope they don't shoo away people with smaller budgets.

I did contemplate buying a solar hybrid A/C when I purchased my A/Cs last year, however, our usage is so little we didn't bother - 2-1/2 months of summer, daily use for 8 hours. So just got ourselves 2 regular split-A/Cs.

[SirAlec]

This what he is doing.
:: WELCOME TO InSolTherm Times ::

at this site.
The Way to Reach God (BK Multimedia Services)

will find more details when he comes back, he is in some conference abroad.

[NPV]

Interesting thread !
As folks here have explained, the cost of such systems is generally what puts us off. Also, its a given that we need good batteries to store the excess power generated during the day but the need for converting to AC is another issue that adds to efficiency and cost of the system.
I know several folks who have made a small start at least with lighting needs in their homes - they have solar panels, CFL/Led lights and DC wiring running in the house to power these lights - here again if aesthetics is of concern you will end up spending more to conceal the wiring unless you have planned it during construction.
I also came across a company's website recently who now sell 3 light, 5 light solar lighting systems with LED bulbs. Will share more details as soon as I find it.

[null]

Hey, I too have been thinking of this solar PV based setup for home. I have a friend who has a simple DC lighting setup (don't know the configuration of the battery/panel) which is used in parallel to the AC lighting in their house.
I think a four 5W CFL and one xW LED setup with a PV panel (guess it is about 10W going by its size) and battery was around 20K. The sad part of this light setup was that the CFL light was not adequate.

If building a house newly, better make provision for a DC lighting wiring upfront (parallel) which can be used for off-grid lighting.

Coming the PV panel & battery sizing calculation, here is a write up which gives you the approach for this computation:
http://www.leonics.com/support/artic...es2_12j_en.php