✅ Hybrid System with Grid Backup (Optional)
✅ Higher Efficiency Panel & Battery Options
✅ Expanded Cost Breakdown & ROI Estimation
✅ Financing & Payback Period Calculation

1. Power Consumption Calculation

• Cooktop Power Rating: 5000W (5kW)
• Daily Usage: 6 hours
• Total Energy Consumption Per Day: 5000W×6 hours=30,000Wh (30kWh)5000W \times 6 \text{ hours} = 30,000Wh \text{ (30kWh)}5000W×6 hours=30,000Wh (30kWh)
• Total Energy Consumption Per Month: 30,000Wh×30 days=900,000Wh (900kWh)30,000Wh \times 30 \text{ days} = 900,000Wh \text{ (900kWh)}30,000Wh×30 days=900,000Wh (900kWh)

2. Battery Requirement Calculation

(A) Lead-Acid Battery Option

• System Voltage: 72V
• Total Required Battery Capacity (Ah): 30,000Wh72V=417Ah\frac{30,000Wh}{72V} = 417Ah72V30,000Wh​=417Ah
• Battery Configuration:
  • Using 12V, 100Ah batteries
  • To achieve 72V system, 6 batteries must be connected in series
  • To meet 417Ah, we need 5 parallel sets of 6 batteries
  • Total Batteries Required: 6×5=30 batteries6 \times 5 = 30 \text{ batteries}6×5=30 batteries

• Battery Cost Calculation:
  • Estimated cost per 12V 100Ah battery: $146
  • Total Battery Cost: 30×146=$4,38030 \times 146 = \mathbf{\$4,380}30×146=$4,380

(B) Lithium-Ion Battery Option (Higher Efficiency)

• Lithium batteries last 2-3 times longer than lead-acid
• Estimated Required Capacity: 72V, 210Ah (equivalent to 417Ah Lead-Acid due to efficiency)
• Cost per 72V 100Ah Lithium Battery: $1,200
• Total Batteries Required: 2.1 units (rounded up to 3)
• Total Lithium Battery Cost: 3×1200=$3,6003 \times 1200 = \mathbf{\$3,600}3×1200=$3,600

3. Solar Panel Requirement Calculation

• Solar Power Needed (with 5 Hours of Peak Sunlight): 30,000Wh5 hours=6000W\frac{30,000Wh}{5 \text{ hours}} = 6000W5 hours30,000Wh​=6000W
• Solar Panels Required:
  • Each 200W panel produces 200W × 5 hours = 1000Wh (1kWh) per day
  • Total Panels Required: 30,000Wh1000Wh=30 panels\frac{30,000Wh}{1000Wh} = 30 \text{ panels}1000Wh30,000Wh​=30 panels
• Solar Panel Cost Calculation:
  • Estimated cost per 200W panel: $60
  • Total Solar Panel Cost: 30×60=$1,80030 \times 60 = \mathbf{\$1,800}30×60=$1,800

4. Charge Controller Requirement

• Required Charge Controller:
  • 72V system requires a charge controller with at least 100A capacity
  • Estimated cost for a 100A Charge Controller: $150

5. Backup Generator Option (Recommended for Emergencies)

• For emergency cooking at night or on cloudy days
• Recommended Generator: 5kW Solar Hybrid Generator
• Estimated Cost: $1,200

6. Cables & Accessories Cost

• High-capacity solar cables, connectors, battery wiring: $100

7. Installation & Maintenance Costs

• Installation (Labor, Panel Mounting, Wiring): $200
• Annual Maintenance (Battery Check, Cleaning Panels): $100

8. Hybrid Grid Backup (Optional)

• If solar power is insufficient, a hybrid grid inverter can be used
• 72V Hybrid Inverter Cost: $600

9. Total System Cost Breakdown

10. Payback Period & ROI

• Monthly Cost Savings from Grid Electricity (Assuming $0.10/kWh): 900kWh×0.10=$90/month900kWh \times 0.10 = \mathbf{\$90/month}900kWh×0.10=$90/month
• Annual Savings: 90×12=$1,080/year90 \times 12 = \mathbf{\$1,080/year}90×12=$1,080/year
• Payback Period for Lead-Acid System: 8,7301,080=8.1 years\frac{8,730}{1,080} = \mathbf{8.1 \text{ years}}1,0808,730​=8.1 years
• Payback Period for Lithium-Ion System: 7,9501,080=7.4 years\frac{7,950}{1,080} = \mathbf{7.4 \text{ years}}1,0807,950​=7.4 years
• Battery Replacement Costs:
  • Lead-Acid: Every 3-5 years
  • Lithium-Ion: Every 10+ years
  • Lithium option is better in long-term savings

11. Conclusion & Recommendations

✅ Best Choice for Long-Term Efficiency:

🔹 Lithium-Ion Option ($7,950) – Lower maintenance, longer lifespan, better ROI
🔹 Hybrid Grid Backup ($600) – Ensures uninterrupted cooking during cloudy days
🔹 Backup Generator ($1,200) – Optional for off-grid emergencies
🔹 Total Investment: $8,730 (Lead-Acid) or $7,950 (Lithium-Ion)
🔹 Break-even Time: 7-8 Years with ROI