app.py

import streamlit as st

# Title of the app
st.title("Complete Solar Energy Calculator")

# Input Section: User inputs for energy usage, costs, etc.
st.header("Enter your energy usage and system parameters:")

# Currency selection
currency = st.selectbox("Select your currency:", ["USD", "EUR", "INR", "GBP", "AUD", "CAD", "JPY", "PKR", "Other"])

# Average Monthly Usage in kWh
monthly_usage = st.number_input("Enter your average monthly energy usage (kWh):", min_value=0.0)

# Peak Demand in kW
peak_demand = st.number_input("Enter your peak demand (kW):", min_value=0.0)

# Solar Panel Efficiency
solar_panel_efficiency = st.number_input("Enter the efficiency of your solar panels (0 to 100):", min_value=0.0, max_value=100.0)

# Panel Output in Watts (W)
panel_output_watts = st.number_input("Enter the solar panel output (in watts, W):", min_value=0)

# Average Sunlight Hours per Day
sunlight_hours = st.number_input("Enter the average sunlight hours per day:", min_value=0.0)

# Inverter Cost (user input)
inverter_cost = st.number_input(f"Enter the cost of the inverter (in {currency}):", min_value=0.0)

# Cost per Solar Panel
panel_cost = st.number_input(f"Enter the cost per solar panel (in {currency}):", min_value=0.0)

# Calculate Inverter Capacity based on Peak Demand (will be done once peak demand is entered)
if peak_demand > 0:
    inverter_capacity = peak_demand * 1.2  # Inverter capacity should be around 1.2 times the peak demand for efficiency
    st.write(f"Recommended Inverter Capacity: {inverter_capacity:.2f} kW (1.2 times peak demand)")

# Button to trigger the calculations
calculate_button = st.button("Calculate Solar Energy System")

if calculate_button:
    # Perform calculations when the button is clicked
    if panel_output_watts > 0 and sunlight_hours > 0:
        # Determine Annual Energy Consumption (in kWh)
        annual_energy_consumption = monthly_usage * 12

        # Calculate Daily Energy Requirement (in kWh)
        daily_energy_requirement = annual_energy_consumption / 365

        # Solar Panel Output in kWh per day (considering the sunlight hours)
        solar_panel_output_kwh = (panel_output_watts / 1000) * sunlight_hours  # Convert watts to kWh

        # Calculate the number of panels required
        num_panels_required = daily_energy_requirement / solar_panel_output_kwh

        # Cost Calculations
        total_solar_cost = num_panels_required * panel_cost
        total_inverter_cost = inverter_cost

        # Total Solar System Installation Cost
        total_installation_cost = total_solar_cost + total_inverter_cost

        # Payback Period Calculation
        cost_per_kwh = st.number_input(f"Enter the cost per kWh of electricity (in {currency}):", min_value=0.0)
        annual_savings = annual_energy_consumption * cost_per_kwh
        payback_period = total_installation_cost / annual_savings if annual_savings > 0 else float('inf')

        # Display Results
        st.header("Results:")

        st.subheader(f"Annual Energy Consumption: {annual_energy_consumption:.2f} kWh")
        st.subheader(f"Daily Energy Requirement: {daily_energy_requirement:.2f} kWh")
        st.subheader(f"Solar Panel Output per day: {solar_panel_output_kwh:.2f} kWh")
        st.subheader(f"Number of Panels Required: {num_panels_required:.2f} panels")
        st.subheader(f"Inverter Capacity Required: {inverter_capacity:.2f} kW")
        st.subheader(f"Total Solar Panel Cost: {total_solar_cost:.2f} {currency}")
        st.subheader(f"Total Inverter Cost: {total_inverter_cost:.2f} {currency}")
        st.subheader(f"Total Installation Cost: {total_installation_cost:.2f} {currency}")
        st.subheader(f"Payback Period: {payback_period:.2f} years")

    else:
        st.warning("Please ensure that both solar panel output and sunlight hours are greater than 0.")

# Show tips for improving the app or using it effectively
st.markdown("""
- Make sure to input accurate data to get the most reliable results.
- The inverter capacity is calculated based on your peak demand.
- Payback period assumes that energy savings will remain constant each year.
""")