Roof Top Solar PV Power system-Technical and economical analysis

Maruntech enterprisesChennai

Objective

• Technical details• Economic benefits– Domestic customers– Commercial customers– Industrial customers

Solar energy

• Every hour the earth reflected back more sunlight than what is used by the entire population in one year.

• If we covered the Sahara Desert with the photovoltaic cells, we could cover all the energy requirements of the earth!

Global Energy situation

Uranium Natural Gas

Oil Coal

Annual Energy from the Sun

Annual Energy Demand

Equi

vale

nt S

tock

of E

nerg

y So

urce

Stand alone PV system

Source(PV array)

Inverter Load

BatteryCharge

Controller

Battery Bank

Grid SupplyIn case of

Emergency

S1 S2

S3

Working Mechanism

SOLAR POWER

• FROM SUN

BATTERY• CHARGING

INVERTER• DC to AC

LOAD• AC LOAD

DURING DAY

BATTERY • DISCHARGING

INVERTER• DC TO AC

LOAD• AC LOAD

DURING DARK

Solar Power plant

Factors affecting performance

• Light Intensity• Shading• Cell Temperature• Angle of Sunlight• Improper Wiring• The immediate environment and geographic location• Nearby mountains, hills, trees, tall buildings etc may

considerably reduce the number of hours of direct sunshine that the panels receive.

PV Economics• PV unit : Price per peak watt (Wp) ( Peak watt is the amount of power output a PV module

produces at Standard Test Conditions (STC) of a module operating temperature of 25°C in full noontime sunshine (irradiance) of 1,000 Watts per square meter )

• A typical 1kWp System produces approximately 1600-2000 kWh energy in India

• One unit of solar power costs around Rs. 7.5-12

Comparison with Diesel and utility grid

Tamilnadu Solar Policy - brief• Investment Subsidy of Rs.20000/kW addon to 30%

investment subsidy from MNRE• Incentive for roof top power plant– Rs. 2 per unit for first 2 years– Rs. 1 per unit for next 2 years– Rs. 0.50 per unit for subsequent 2 years– For All solar or Solar – wind hybrid power plant

• Solar Power obligations (SPO)– 6% of the consumption through solar for HT – Generate through captive power plant– Or Purchase from any third party having Solar PP

• All government and local bodies building should have roof top solar power plant

• All streetlights and water supplies installations in local bodies should be energized by solar power

• Exemption from electricity tax for 100% on electricity generated by solar power projects will be allowed for 5 years

• Exemption from demand cut to the extent of 100% of the installed capacity for all captive PV power owned industries

Parameters Data Assumption

Solar Plant capacity 1kW

Area required 11sq.m

Capital cost in INR 1,20,000 Rs. 120/Wp without battery

Subsidy from MNRE in INR 36,000 30% of the capital

Subsidy from TNGOV in INR 20,000 Rs.20000/kW

Net Investment in INR 64,000

Units generated per day 6 Assuming 6hours of sunshine

Units generated per year 1800 Assuming 300days of operation

EB cost from grid in INR 6300 Rs.3.5/unit

Rebate/year TNGOV in first 2 years 3600 Rs. 2/unit

Investment remaining after 2 years 44,200

Rebate/yearTNGOV in next 2 years 1800 Rs. 1/unit

EB cost from grid after two years 6552 Assuming 4% increase in tariff

Investment remaining after 4 years 27496

Rebate/year -TNGOV in next 2 years 900 Rs. 0.50/unit

EB cost from grid after 4 years 6814 Assuming 4% increase in tariff

Investment remaining after 6 years 12068

EB cost from grid after 6years 7087 Assuming 4% increase in tariff

Payback period 7 years 8 months

Parameters Data Assumption

Solar Plant capacity 1kW

Area required 11sq.m

Capital cost in INR 1,20,000 Rs. 120/Wp without battery

Subsidy from MNRE in INR 36,000 30% of the capital

Subsidy from TNGOV in INR 20,000 Rs.20000/kW

Net Investment in INR 64,000

Units generated per day 6 Assuming 6hours of sunshine

Units generated per year 1800 Assuming 300 days of operation

EB cost if consumed from grid in INR 12600 Rs.7/unit

Rebate/year TNGOV in first 2 years 3600 Rs. 2/unit

Investment remaining after 2 years 31,600

Rebate/year TNGOV in next 2 years 1800 Rs. 1/unit

EB cost if consumed after 2 years 13104 Assuming 4% increase in tariff

Investment remaining after 4 years 1792

Rebate/year TNGOV in next 2 years 900 Rs. 0.50/unitPayback period 4 years 2 months

Parameters Data Assumption

Solar Plant capacity 1kW

Area required 11sq.m

Capital cost in INR 1,20,000 Rs. 120/Wp without battery

Subsidy from MNRE in INR 36,000 30% of the capital

Subsidy from TNGOV in INR 20,000 Rs.20000/kW

Net Investment in INR 64,000

Units generated per day 6 Assuming 6hours of sunshine

Units generated per year 1800 Assuming 30 days of month

DG unit cost if consumed in INR 27000 Rs.15/unit

Rebate/year TNGOV in first 2 years 3600 Rs. 2/unit

Investment remaining after 2 years 2800

Rebate/year TNGOV in next 2 years 180 Rs. 1/unit

Rebate/year TNGOV in next 2 years 90 Rs. 0.50/unit

Payback period 2 years 1 month