How Many Units Does Solar Panel Generate? Complete Guide for 1kW, 3kW, 5kW, 10kW
How much electricity do solar panels generate? How many units per day for 1kW, 3kW, 5kW and 10kW systems? What is the cost per unit? Complete calculation and net cost after subsidy.
How Many Units Does Solar Panel Generate? Complete Guide
This is the most common question every customer asks - "How much electricity do solar panels generate?" What is the cost per unit of solar electricity? How much does it cost to install a solar system? Let's understand in detail. With subsidy under PM Surya Ghar Yojana in Uttar Pradesh, solar electricity becomes very affordable.
📑 In this article:
- What is 1 Unit of Electricity?
- How many units do 1kW-10kW systems generate?
- How to calculate generation?
- How many units does one solar panel generate?
- What is the cost per unit of solar?
- Solar vs Grid Electricity - Which is cheaper?
- Which kW system do I need for my bill?
- Real savings calculation with examples
- Frequently Asked Questions
What is 1 Unit of Electricity?
First, let's understand what a "unit" is. In electricity terms, 1 Unit = 1 Kilowatt-hour (kWh).
📖 Simple Explanation:
1 Unit = Electricity consumed by a 1000 Watt appliance running for 1 hour
- 1000 Watt heater running for 1 hour = 1 Unit
- 100 Watt bulb running for 10 hours = 1 Unit
- 40 Watt fan running for 25 hours = 1 Unit
- 1.5 Ton AC (1500 Watt) running for 40 minutes = 1 Unit
📊 Cost of 1 Unit in UP:
- 0-150 units: ₹5.50 per unit
- 151-300 units: ₹6.50 per unit
- 301-500 units: ₹7.50 per unit
- Above 500 units: ₹8.00+ per unit
Average residential rate: ₹7.00 per unit | Commercial rate: ₹8.50 per unit
How many units do 1kW to 10kW systems generate?
Uttar Pradesh receives an average of 5.2 hours of good sunlight per day. Below is detailed generation for all system capacities:
| System Capacity | Daily (Theoretical) | Daily (Practical) | Monthly | Yearly | 25-Year |
|---|---|---|---|---|---|
| 1kW | 5.2 units | 4.4 units | 132 units | 1,606 units | 40,150 units |
| 2kW | 10.4 units | 8.8 units | 264 units | 3,212 units | 80,300 units |
| 3kW | 15.6 units | 13.3 units | 399 units | 4,818 units | 1,20,450 units |
| 4kW | 20.8 units | 17.7 units | 531 units | 6,424 units | 1,60,600 units |
| 5kW | 26.0 units | 22.1 units | 663 units | 8,030 units | 2,00,750 units |
| 6kW | 31.2 units | 26.5 units | 795 units | 9,636 units | 2,40,900 units |
| 8kW | 41.6 units | 35.4 units | 1,062 units | 12,848 units | 3,21,200 units |
| 10kW | 52.0 units | 44.2 units | 1,326 units | 16,060 units | 4,01,500 units |
🔆 Please Note:
Practical generation is 15% lower than theoretical due to panel efficiency, wiring losses, inverter losses, and dust effects. Actual generation depends on weather, shade, and maintenance.
How many units does one solar panel generate?
Today, 540-550 Watt solar panels are common. Let's see how much one panel generates:
| Panel Wattage | Daily Generation (5.2 hrs sun) | Monthly | Yearly |
|---|---|---|---|
| 400 Watt | 2.08 units | 62.4 units | 759 units |
| 450 Watt | 2.34 units | 70.2 units | 854 units |
| 500 Watt | 2.60 units | 78.0 units | 949 units |
| 545 Watt | 2.83 units | 84.9 units | 1,033 units |
| 550 Watt | 2.86 units | 85.8 units | 1,044 units |
📌 How many panels for 3kW system?
3000 Watts ÷ 545 Watts per panel = Approximately 6 panels
6 panels × 2.83 units daily = 16.98 units/day (theoretical) | 6 × 2.40 units = 14.4 units/day (practical)
How to calculate solar generation? (Simple Formula)
📐 Generation Formula:
Daily Generation (Units) = System Capacity (kW) × Average Sun Hours × Panel Efficiency Factor
Average sun hours for UP: 5.2 (6+ in Apr-May, 4.5 in Dec-Jan)
Panel efficiency factor (Mono PERC): 0.85 (assuming 15% loss)
Example 1: 3kW system
3 × 5.2 × 0.85 = 13.26 units/day
13.26 × 30 = 398 units/month | 13.26 × 365 = 4,840 units/year
Example 2: 5kW system
5 × 5.2 × 0.85 = 22.1 units/day
22.1 × 30 = 663 units/month | 22.1 × 365 = 8,066 units/year
What is the cost per unit of solar electricity?
Solar system is a one-time investment that provides electricity for 25 years. To calculate per unit cost, divide total cost by total generation.
| System Capacity | Total Cost | Subsidy | Net Cost | 25-Year Generation | Per Unit Cost |
|---|---|---|---|---|---|
| 1kW | ₹68,335 | ₹45,000 | ₹23,335 | 40,150 units | ₹0.58 |
| 2kW | ₹1,36,670 | ₹90,000 | ₹46,670 | 80,300 units | ₹0.58 |
| 3kW | ₹2,05,000 | ₹1,08,000 | ₹97,000 | 1,20,450 units | ₹0.80 |
| 5kW | ₹3,25,000 | ₹1,08,000 | ₹2,17,000 | 2,00,750 units | ₹1.08 |
| 10kW | ₹6,50,000 | ₹1,08,000 | ₹5,42,000 | 4,01,500 units | ₹1.35 |
⚡ How much cheaper than grid electricity?
Grid electricity rate: ₹7.00 per unit (residential) | ₹8.50 per unit (commercial)
Solar electricity rate: ₹0.58 to ₹1.35 per unit
Savings: 80-90% cheaper than grid! You save ₹6-7 on every unit.
Solar vs Grid Electricity - Complete Comparison
| Parameter | Grid Electricity | Solar Electricity (After Subsidy) |
|---|---|---|
| Per Unit Cost | ₹5.50 - ₹8.00+ | ₹0.58 - ₹1.35 |
| Monthly Cost for 3kW | ₹2,500 - ₹3,500 | ~₹0 (only EMI possible) |
| 25-Year Cost (3kW) | ₹7,50,000 - ₹10,50,000 | ₹97,000 (one time) |
| Annual Rate Increase | 5-8% increase every year | No increase ever |
| Environmental Impact | CO2 emission | Zero pollution |
Which kW system do I need for my monthly bill?
| Your Monthly Bill | Your Consumption (Units) | Recommended Capacity | Cost After Subsidy |
|---|---|---|---|
| ₹1,500 - ₹2,000 | 200-280 units | 1-2 kW | ₹23,000 - ₹47,000 |
| ₹2,000 - ₹3,000 | 280-420 units | 2-3 kW | ₹47,000 - ₹97,000 |
| ₹3,000 - ₹5,000 | 420-700 units | 3-4 kW | ₹97,000 - ₹1,50,000 |
| ₹5,000 - ₹7,000 | 700-1000 units | 5-6 kW | ₹2,17,000 - ₹2,60,000 |
| ₹7,000 - ₹10,000 | 1000-1400 units | 8-10 kW | ₹3,50,000 - ₹5,42,000 |
Real Savings Calculation with Examples
🏠 Example 1: Home with 3kW system (Monthly bill ₹2,500)
System Cost: ₹1,90,000
Subsidy: ₹1,08,000
Your Investment: ₹82,000
Daily Generation: 13.3 units
Monthly Generation: 399 units
Monthly Savings: 399 × ₹7 = ₹2,793
Payback Period: ₹82,000 ÷ ₹2,793 = 29 months (2.4 years)
Total 25-Year Savings: ₹8,37,900 - ₹82,000 = ₹7,55,900
🏭 Example 2: Office with 5kW system (Monthly bill ₹5,000)
System Cost: ₹3,25,000
Subsidy: ₹1,08,000
Your Investment: ₹2,17,000
Daily Generation: 22.1 units
Monthly Generation: 663 units
Monthly Savings: 663 × ₹8.5 = ₹5,635
Payback Period: ₹2,17,000 ÷ ₹5,635 = 38 months (3.2 years)
Total 25-Year Savings: ₹16,90,500 - ₹2,17,000 = ₹14,73,500
🏡 Example 3: Small Home with 1kW system (Monthly bill ₹1,000)
System Cost: ₹68,335
Subsidy: ₹45,000
Your Investment: ₹23,335
Monthly Generation: 132 units
Monthly Savings: 132 × ₹7 = ₹924
Payback Period: ₹23,335 ÷ ₹924 = 25 months (2.1 years)
Total 25-Year Savings: ₹2,77,200 - ₹23,335 = ₹2,53,865
Frequently Asked Questions (Most Common User Questions)
❓ How many units does a 1kW solar panel generate in one day?
A 1kW solar panel generates an average of 4.4 to 5.2 units per day in UP. In summer (Apr-May): 5.5-6 units, in winter: 3.5-4 units.
❓ How much time does a solar panel take to generate 1 unit?
A 545 Watt panel takes approximately 1 hour 50 minutes to generate 1 unit. A 400 Watt panel takes 2.5 hours.
❓ How many units does a 3kW solar system generate in 1 hour?
A 3kW system theoretically generates 3 units per hour. Practically, 2.5-2.7 units per hour (due to panel efficiency, temperature, and wiring losses).
❓ How much does it cost to generate 1 unit of solar electricity?
After subsidy, solar electricity costs ₹0.58 to ₹1.35 per unit. Grid electricity is ₹7.00. Solar is 80-90% cheaper.
❓ Do solar panels generate power on rainy or cloudy days?
Yes, but less. Light rain/clouds give 50-60% of sunny day generation, heavy rain/dense clouds give 30-40%. Zero generation at night - need grid or battery then.
❓ How much does a 1kW solar system cost?
1kW system costs ₹61,670 - ₹75,000. After ₹45,000 subsidy, your investment becomes ₹16,670 - ₹30,000.
❓ What can we run in 1 unit of electricity?
In 1 unit: 10 LED bulbs for 1 hour, OR 1 fan for 25 hours, OR 1 TV for 5 hours, OR 1 fridge for 4 hours, OR 1 AC for 40 minutes, OR mobile charger for 200 hours.
❓ Can a solar system store electricity?
No, a regular on-grid solar system does not store electricity. Excess electricity is sold to the grid. At night, you take electricity from the grid. If you want to store electricity, you need a battery (hybrid system).
❓ What is the lifespan of solar panels?
Good Mono PERC panels last 25-30 years. Even after 25 years, they maintain 80-85% efficiency.
Know the generation for the right solar system for your home
PN Kinetic Sunrise experts will visit your site and tell you how many units your roof can generate and how much you will save. Book a free site visit today.