[avisidhu]

As per info present at Punjab Energy Development Agency, average cost for a 2KW solar installation is around 1.70 to 1.85L, and a 45K discount is given for the same. Up north the sun shines practically throughout the year, so only solar should be good enough. And at 1.20 odd lakh, don't think its a bad deal at all:

http://www.netmeteringpunjab.com/illustration.html

What could make it a no brainer however, is if this unit could run even one AC. It can be such a boon during the scorching summers to have one AC run since morning, and keep the house relatively cool without a hole in the pocket. But doesn't look feasible based on the current tech for AC's.

[avingodb]

http://www.mnre.gov.in/solar-mission...ntroduction-2/

This page of MNRE, GOI has a lot of information for those interested in the subject.

[Screwdriva]

Originally Posted by vagabond128

I was thinking if I am paying Rs.1500 per month as electricity bill. It would take me more than 16 years to recover my cost. If I factor in other costs like, maintenance, replacements and interest loss, recovery period would increase further.

Isn't that costly? Am I missing something in my calculcations?

If you pay only Rs. 1500 for electricity, it makes no sense to invest in a solar system unless you plan on using an electric vehicle like a Reva or an electric 2 wheeler. Then, again, the monthly fuel costs can be completely covered by a 2KV renewable energy system, enhancing your ROI period dramatically.

Originally Posted by aamateen46

Excellent thread Screwdriva! Thanks for sharing.
I feel that awareness of this new way of living is the need of the hour. Only then will the demand increase and will result in increase in supply and easy availability of the overall infrastructure.
This will then pave way for large-scale adoption thereby reaping its huge benefits for our country as a whole!

Educating all with the information given in this thread is indeed a very helpful gesture towards the right direction.

Thanks for your kind words. Indians are naturally one of the most environmentally responsible people and I am confident that even the current 6-7 year recovery period will excite most of us to embrace renewable technology.

Originally Posted by explorer09

For residential use, Solar hasn't yet reached grid parity in India. So yes, the payback period is very high so you should only go for it for the satisfaction of doing something for the environment.

Solar makes perfect sense for commercial/industrial units though even at today's prices at least in most states in India.

There are other benefits as well. You never have to worry about power cuts, your batteries on your devices (e.g. laptops) last much longer because of the friendly nature of renewable energy towards batteries. If you use an EV, your payback period is greatly reduced because of the high price of petrol. Otherwise, a 6-7 year payback period is realistic at today's prices.

Originally Posted by cooldude1988765

From what I understand, a huge part of installing your own solar roof top panels is the cost of batteries.

Telangana state has a net metering option where your excess power produced is sold to the discom. This allows you to do away with the batteries completely.

For example if you produce 200 units of solar power and consume 300 units totally every month you would only pay for the difference that is 100 units.
What I assume is there will be a huge difference in the bill amount owing to the slab based consumption charges.

Below is an excerpt from the Telangana state solar power policy.

An acquaintance lives in a Solar Apartment Complex. His power bill is usually in the Rs.50-100 range every month and around 700-800 in the summer months in spite of using 3 ACs.



For those intersted in the whole policy here is the link.

Battteries, from even the best brand, comprise 10-15% of the cost of the system

What you describe is called a smart grid and is unique to Telangana, if what you say is true. It allows for sale of power back into the grid and is the way of the future. It is what allows US residents to earn profit on their systems.

Originally Posted by avisidhu

As per info present at Punjab Energy Development Agency, average cost for a 2KW solar installation is around 1.70 to 1.85L, and a 45K discount is given for the same. Up north the sun shines practically throughout the year, so only solar should be good enough. And at 1.20 odd lakh, don't think its a bad deal at all:

http://www.netmeteringpunjab.com/illustration.html

What could make it a no brainer however, is if this unit could run even one AC. It can be such a boon during the scorching summers to have one AC run since morning, and keep the house relatively cool without a hole in the pocket. But doesn't look feasible based on the current tech for AC's.

1.2 Lakhs is less than half the price I paid 10 years ago. Inverter AC's may be possible with a 8-10 Lakh spend. I don't know for sure because I never tried. I do know that inverters do support ACs, so it is theoretically possible.

Originally Posted by hangover

This article is useful.

Could you please tell us what voltage you use? Is it 12v or higher like 24 or 48?

I'm using 24V but this is rare.I believe most systems are 12V

Originally Posted by hangover

Did you replace your regular fridge with an inverter type model? These don't need an initial surge of 1300-1500 W at compressor start up against a steady state consumption of of 300 W or so.

When I installed my system, inverter fridges didn't exist So the system had to be able to handle the initial surge of a compressor.

Originally Posted by hangover

The panels themselves - are they robust enough to clean dust and bird droppings by just a gentle cloth wipe down? Or say with a long handled thin rubber wedge (like the one used to clean car windshields)? Any chance of electrocution at its power output location?

No chance of electrocution with solar panels and yes, all non-amorphous panels are very durable and have only gotten better in terms of construction. I recommend Tata BP Solar as they are high(er) efficiency and durable

Originally Posted by hangover

I'm assuming you don't drain the batteries below 50% of full charge. If you use power all night then will the batteries get recharged fully by day? Because these are used 24 X 7? Most invertors are used only when you don't receive municipality power.

Please let us know the cost of replacing the full set of batteries every 6-7 years. Say around 60-70k?

My batteries are recharged every day by my power plant. When there is no wind, this takes longer as I have a 1 KV wind turbine as well. You should budget for around Rs. 25K at most for the best batteries available

Originally Posted by hangover

Do you get power measurement meters in India? I haven't seen any which the public could buy. The reason I ask is if one installs this for a multi tenant building then the cost of maintenance and eventual replacement could be shared based on consumption.

Good question. I'm sorry to say that I'm not aware of this as I've never thought to suggest a shared power plant given how political Indian societies can be.

[slamnos]

Embedding solar panels on EVs for charging is still not effective, mainly due to following reasons:

1. Size of Panels have to be much larger than what the car body panels can hold
2. Panels have to be stationary to get the most out of solar power

However higher capacity solar panels can be installed at homes which can charge your car overnight, I believe Mahindra Electric is already offering one such thing.

Another important point, few EVs globally can be plugged to an inverter and can be used as UPS during power cuts (smart solution) I believe similar setup can be done here as well.

[Mohd Faiz]

Originally Posted by Screwdriva

an optional small wind turbine for those cloudy, windy monsoon days (not required but highly recommended).

Thanks for sharing. Is there any noise issue with the wind turbine?. The typical 3 blade wind turbine makes noise while blade moves across the pole. Or the design is different for the small unit you are using?.

[Screwdriva]

The Southwest 3 blade turbine I use is from the "Whisper" series, known to be very quiet. No noise for 9 months of the year with a faint noise during the monsoon (similar to the sound of the blades of a table fan at home).

I would also add that solar panels on EVs are not a lost cause. Toyota used to provide vehicle ventilation on the Prius via solar panels. They would work well as a trickle charge mechanism...nothing more.

[raghubhaskar]

This is a really good initiative, going green is the way of the future..!

Since you said you have an off the grid setup, during the day time the fans and lights in your home are run using solar panels directly and they charge the batteries also for the night?

[Screwdriva]

Originally Posted by raghubhaskar

Since you said you have an off the grid setup, during the day time the fans and lights in your home are run using solar panels directly and they charge the batteries also for the night?

The system always runs off the batteries and will charge whenever a power source is available (wind is available at night ass well)

[Sutripta]

Originally Posted by Screwdriva

your batteries on your devices (e.g. laptops) last much longer because of the friendly nature of renewable energy towards batteries.

Could you explain this one please?

Regards
Sutripta

[mvadg]

Originally Posted by avisidhu

...
if this unit could run even one AC. It can be such a boon during the scorching summers to have one AC run since morning, and keep the house relatively cool without a hole in the pocket. But doesn't look feasible based on the current tech for AC's.

Absorption/Absorbtion technology for cooling (Thermax does this with waste heat). SolarFrost in Austria has some solutions with much better efficiency using solar energy.

[Screwdriva]

Originally Posted by mvadg

Absorption/Absorbtion technology for cooling (Thermax does this with waste heat). SolarFrost in Austria has some solutions with much better efficiency using solar energy.

Visit the THANE municipal HQ for proof that Absorption/ Absorption doesn't work in all but the most extremely hot environments. The municipality of Thane spent crores on their system and its just a showpiece

[Holyghost]

Originally Posted by Screwdriva

India does not have a smart grid. Therefore, it is not possible for IN systems to route excess power back to the grid. This does exist in Western countries and allow for renewable energy systems to earn income for owners by selling back power during the day.

Thanks for starting the thread Screwdriva. Grid tie setup has already started in India. I have already installed a 3KW Grid Tie setup which do not need batteries. Depending on the State you are in, there is a list of approved vendors by the electricity company. My solar setup is in Kerala and from among 10+ approved vendors (including Tata Solar, Bosch, Schneider etc). I went with Su-kam.

For Bangalore, you can refer this link for approved vendors.
http://bescom.org/en/list-of-inverter-manufacturers/

For Kerala, You can go via the ANERT
The list of approved vendors are here.

Setup:
The grid tie system involves 3 major parts.
The Solar Panels
Grid Tie Inverter
2 way Electricity Meter

The advantage of this system is that you are not limited by the capacity of your solar system unlike a battery based system. Everything is connected to your mains line and your grid (bescom) acts as your battery. You can run your AC and all other equipments just the way you use normally.

When you have excess solar, that excess goes back to your grid. Your 2 way meter runs backward when you are sending power back to the grid. During night and during high power consumption, you pull power from the grid and the 2 way meter runs forward. So at the end of the month, your electricity bill is the net of power you consumed minus the power you produced.

Some points to note:

• Grid-tie works only when you have mains supply. This is for safety of the power grid workers because you should not continue to send electricty to the grid during a maintenance or blackout. So in short, you cannot use your solar power during a blackout.
  However you can use your normal inverter or the latest hybrid grid-tie inverter(expensive) for power during outage.
  I am working on adding a separate setup (DIY) to use my solar panels during a power outage. I will give you the details once I have that setup working.

• Bangalore pays the customers the highest in the country for excess power produced. At the end of the month, if your net production is > net usage, bescom pays Rs9 per unit send back to grid. In contrast, Kerala pays Rs2 per unit to me.

• The costs quoted by the Solar vendors are inflated if you go for subsidy. In my case, the cost quoted for 3KW setup was 3.1 Lakhs and after subsidy it came to 2.09 L. However, after negotiation they installed the setup for 2.2L since I decided not to wait for subsidy. In Kerala, for subsidy they have a queue system and my number was around 1000+ which could mean a 6 month delay.If you go via subsidy route, there is not much scope for negotiation.

Approximate costs: as of February 2016
Solar panels: 12x250w Sukam: 144000 (MRP: 17000 per panel)
3KW Su-Kam Grid Tie Inverter: Rs 50000 (MRP 85000)
Product Link:
2 way Net Meter: 6000
Wiring+Installation: 10000
Approvals + Misc: 5000

Total: 2.15Lakhs for 3KW system (No Subsidy applied).

[hangover]

Thanks for patiently helping out in answering our questions screwdriva.

I was speaking with a friend who has a camper in the UK. These are called recreational vehicles or RV's in the US.

He lives totally off the grid. He recommended using "built for RV" electrical appliances even for normal homes.
These are 24v or 48v devices. Using these custom devices for the camper his drain on the batteries is drastically reduced.

I'm not very familiar with electrical conversions but he did say that transforming the generated voltage to 230v used in ISI grade appliances causes substantial losses.

Off grid story: a bloke was studying for his Electrical exam. Someone recommended that he remember a poem - twinkle twinkle little star power equals I square R. From this, other equations could be derived.
When the results came. Failure. He had used the line - little star up in the sky. Power equals R square I.

[Screwdriva]

Originally Posted by hangover

Thanks for patiently helping out in answering our questions screwdriva.

It's a genuine pleasure. As I said before, I believe Indians are the most environmentally and economically responsible people and renewable energy fits both criteria well

Originally Posted by hangover

He lives totally off the grid. He recommended using "built for RV" electrical appliances even for normal homes.
These are 24v or 48v devices. Using these custom devices for the camper his drain on the batteries is drastically reduced.

I'm not very familiar with electrical conversions but he did say that transforming the generated voltage to 230v used in ISI grade appliances causes substantial losses.

This is partly accurate and why I used a 24V system. However, I would recommend against this today as finding compatible 24V "out of the box" components is harder.

Originally Posted by Holyghost

Thanks for starting the thread Screwdriva. Grid tie setup has already started in India. I have already installed a 3KW Grid Tie setup which do not need batteries. Depending on the State you are in, there is a list of approved vendors by the electricity company. My solar setup is in Kerala and from among 10+ approved vendors (including Tata Solar, Bosch, Schneider etc). I went with Su-kam.
.

Thank you for sharing this. I have been hoping this would happen for 10 years now. Its great that smart grids are available in a few IN States. Would you be able to list them all for us? Also, why did you chose Su-Kam vs. a more global manufacturer?

My only counters to not using a batteries are:

1) Dependence on the grid i.e. if the grid fails, you have no power.
2) Dependence on the rates determined by the government.


That being said, and assuming that the transmission losses do not negative the environment benefits, the positives of supporting ALL appliances far outweigh the negatives and I would strongly advocate this type of a system, especially at the very reasonable price.

[BigBrad]

Great thread with some very informative posts.

I would like to know if we can set up a 2KW or 3KW grid system with just one or two 150Ah batteries to store the power. The power from solar panels & wind turbine will recharge the battery first and power the house during the day. During night time, we draw power from grid and when there is a power outage, the system uses the power from battery. Is this possible to implement such a setup or do we need more batteries to suit the higher power produced?

In the area where I live, power outages are minimal and usually don't last much long. So, my intention is to cover short power outages and still supply excess to grid. And without the burden of too many batteries, their replacement costs and their disposal once the battery has completed it's usable life.