Solar Rooftop System Buying Guide

Consumer VOICE experts present you the most comprehensive solar rooftop system buying guide that tells about the solar panel price, cost of installation of solar panels on rooftop, metering, maintenance, link to the suppliers and contractors and much more.

WHERE TO START FROM FOR SOLAR ROOFTOP SYSTEM?

Currently, there are two ways through which an individual can install a rooftop solar system. One is the capital-expenditure model where an individual needs to make an upfront payment. For those who are unwilling or unable to put up the money, or where rooftop space is limited, there is the renewable energy servicing company (RESCO) model. In this, a terrace owner or group of owners allows a solar developer to install a plant at a common place. The plant is installed, owned and run by the company or investor, and the consumer pays for the cheaper power at around Rs 5 to Rs 6 per unit – this compares favourably against the Rs 7 to Rs 9 per unit for conventional supply from discoms.

INSTALLATION PROCESS OF SOLAR ROOFTOP SYSTEM

Step 01 Apply online.
Step 02 Empanelled agencies will contact you.
Step 03 Empanelled agency does pre-feasibility study.
Step 04 Agency will collect the balance cost payable by  beneficiary  after  deducting  subsidy  payable  by MNRE.
Step  05  Applicant  has  to  pay  connectivity  charges and execute connectivity agreement with NDMC for net metering.

HOW TO CHOOSE A SOLAR ROOFTOP SYSTEM

The type and size of solar rooftop system depends on individual requirements/factors. These include

1. Your power consumption
2. Roof  type  
3. Solar Resource

The right choice will depend on how  much  sunlight  your  area  receives,  your  budget, how  much  conventional  power  you  want  to  offset with solar power, and where the solar panels will be mounted.

Efficiency  is  an  important  parameter.  This  is  a measure  of  the  panel’s  electricity  output  (in  watts) compared  to  its  surface  area  –  basically  how  much solar energy is converted into electrical power, which is usually around 15 per cent to 20 per cent depending upon the sophistication of the panel. Generally, the higher the efficiency, the more power you can get from a given roof area, and you might have lower installation costs too. However, if you have plenty of roof space, you may find it more economical to buy cheaper panels with lower efficiency and just use more of them.

WHAT IS THE SOLAR PANEL PRICE?

The cost of a solar photovoltaic (PY) system will depend on many variables including the system size and the quality of components used. The approximate cost of a 1 kWp (kilowatt peak) rooftop solar PY project ranges from Rs 55,000 to Rs 87,000   for the state of Delhi – this includes   installation   charges   but   excludes   cost   of storage batteries (if required) and subsidy. The overall cost depends on the size of the project as rates are a little lower for a higher-size project. Prices of solar PY systems offered by various vendors can differ significantly.

COST OF EQUIPMENTS FOR A 1 KW OFF-GRID SOLAR SYSTEM

• Solar PY module (250 watt peak [wp] x 4 [number of systems]): Rs 36,000-Rs 40000/-
• PY module mounting structure (1 kW set): Rs 5,000
• Tubular batteries (150 Ah x 2 [number of batteries]): Rs 27,000-Rs 30,000
• Solar inverter (1.5 kilo-volt-amperes [KYA]): Rs 22,000-Rs 25,000
• Cabling and other accessories: Rs 10,000
• Transportation and installation: Rs 10,000
• The above mentioned costs will come with GST @ 5% extra
• Generating units per day = 4-4.5 units
• (Total  project  cost  (subsidy  +  cost  to  consumer)  of  one  off-grid  rooftop  solar  system  works  out  to
• Rs 55,000-Rs 87,000/kWp. Final cost will vary depending on quality of equipments/brands.)

SOLAR PANEL SUBSIDY

There  is  a  subsidy  of  30  percent  of  maximum benchmark cost – which is Rs 75,000 – per kilowatt (kW)   or   the   actual   project   cost,  whichever   is lower,  from  the  ministry  of  new  and  renewable energy (MNRE), to be routed through Solar Energy Corporation  of  India  (SECI). In  Delhi,  the  local contractor   will   charge   you   after   deducting   the government-given   subsidy,   which   they   will   later claim from the government.

WHO ARE THE SUPPLIERS/CONTRACTORS?

Please refer to this link for local agencies in various states:
http://solarrooftop.gov.in/Agencies_list.html

WARRANTIES AND INSURANCE

Most solar electric systems come with a five- year   guarantee   and   25-year   warranty,   but maintenance may be required to comply with a manufacturer’s warranty.

RENEWABLE POWER NET IMPORT/EXPORT BILL

The   consumer   can   download   the   solar   net- metering rooftop application form from the websites of  DISCOMs.  The  consumer  will  receive  a  net import/export bill indicating either net export to the grid or net import from the grid. The consumer will settle the same as per existing norms.

NET METERING

In  net  metering,  the  excess  solar  energy  is exported to the grid. This excess solar energy is  deducted  from  the  energy  imported  from the  grid  subject  to  certain  conditions.  The consumer  pays  for  the  net  energy  imported from the grid. The consumer shall be paid for net energy credits that remain unadjusted at the end of the financial year at the rate of average power purchase cost (APPC) of the distribution licensee for the respective year on provisional basis. The consumer shall settle the same as per existing norms. Discom will pay the consumer for surplus power generated which remain unadjusted at the end of financial year as per existing regulation. The  trued-up  price  by  Delhi  Electricity  Regulatory Commission  (DERC)  was  Rs  5.00  per  unit  for  FY 2015-16.

HOW TO MAINTAIN SOLAR ROOFTOP SYSTEM

Proper  maintenance  of  your  system  will  keep  it running smoothly. Most vendors recommend a yearly maintenance check by your installer.
Solar panel may need to be cleaned in climates with infrequent rainfall.

IMPORTANT TIPS

•   Improve the energy efficiency in your home to save up to 30 per cent on your bills. You can do this by turning off appliances and using energy-efficient appliances/lights.
•   Assess what energy you currently use and the system capacity you need (and can afford).
•   Check if your roof faces the right direction. North-facing panels will produce to their full capacity.
•   Ensure there are no trees, power lines or other structures shading your roof.
•   Try to figure out your system’s payback time.
•   Are  you  planning  to  install  a  storage  battery,  so  you  can  store  the  solar-generated  electricity  for nighttime use? Check the latest calculations on home-battery storage and payback time.
•   Get multiple quotes from installers to ensure you are getting a good deal.
•   Make sure the installer is accredited by the government and that the panel meets the required standards.