Python code for the "Integrating physical devices with IOTA - Peer-to-peer energy trading with IOTA Part 2" tutorial

p2p_energy_trade_p2.py

#!/usr/bin/env python

# Import PyOTA library
import iota
from iota import Address

# Import time
import time

# Import the INA3221 library
import SDL_Pi_INA3221

# Define the INA3221 object
ina3221 = SDL_Pi_INA3221.SDL_Pi_INA3221(addr=0x40)

# Define INA3221 channels
LED_CHANNEL = 1 # The LED is connected to CHN1 on the INA3221 
SOLAR_PANEL_CHANNEL   = 2 # The solar panel is connected to CHN2 on the INA3221

# Hotel owner IOTA seed used for payment transaction
# Replace with your own devnet seed
seed = b"YOUR9SEED9GOES9HERE"

# Solar panel owner reciever address
# Replace with your own devnet reciever address
addr = "MICIKTVQFXDBZARARUUBXY9OBFDCOFBTYXGOWBWYFZIPYVZVPDLMBVKRF9EUSFASVECRT9PBVBMWMZWADPWZPDDLOD"

# URL to IOTA fullnode used when interacting with the Tangle
iotaNode = "https://nodes.devnet.iota.org:443"

# Define IOTA api object
api = iota.Iota(iotaNode, seed=seed)

# Function for retrieving current power consumption from the LED
def get_current_LED_mW():
    try:
        led_voltage_mV = ina3221.getShuntVoltage_mV(LED_CHANNEL)
        led_current_mA = ina3221.getCurrent_mA(LED_CHANNEL)
        led_watts_mW = led_current_mA * led_voltage_mV
        print("Current LED Power Consumption: %.3f mW" % led_watts_mW)
        return led_watts_mW
    except DeviceRangeError as e:
        print(e)

# Function for retrieving current power generation from the solar panel
def get_current_PANEL_mW():
    try:
        panel_voltage_mV = ina3221.getShuntVoltage_mV(SOLAR_PANEL_CHANNEL)
        panel_current_mA = ina3221.getCurrent_mA(SOLAR_PANEL_CHANNEL)
        panel_watts_mW = panel_current_mA * panel_voltage_mV
        print("Current solar panel Power generation: %.3f mW" % panel_watts_mW)
        return panel_watts_mW
    except DeviceRangeError as e:
        print(e)


# Function for sending IOTA payment
def pay(payment_value):
    
    # Display preparing payment message
    print('Preparing payment of ' + str(payment_value) + ' IOTA to address: ' + addr + '\n')
               
    # Create transaction object
    tx1 = iota.ProposedTransaction( address = iota.Address(addr), message = None, tag = iota.Tag(iota.TryteString.from_unicode('HOTELIOTA')), value = payment_value)

    # Send transaction to tangle
    print('Sending transaction..., please wait\n')
    SentBundle = api.send_transfer(depth=3,transfers=[tx1], inputs=None, change_address=None, min_weight_magnitude=9)       

    # Display transaction sent confirmation message
    print('Transaction sendt...\n')
    
# Define some variables
pay_frequency = 60
pay_counter = 0
accumulated_LED_mW = 0.0
accumulated_PANEL_mW = 0.0

# Main loop that executes every 1 second
while True:
    
    # Check if payment round has been completed 
    if pay_counter == pay_frequency:
        
        
        # Calculate average power consumption for this round
        average_LED_mW = accumulated_LED_mW / pay_frequency
        print("*** Average LED Power Consumption: %.3f mW" % average_LED_mW)
        
        # Calculate average solar panel power generation for this round
        average_PANEL_mW = accumulated_PANEL_mW / pay_frequency
        print("*** Average Solar Panel Power Generation: %.3f mW" % average_PANEL_mW)
        
        # Calculate energy price (10 IOTA's devided by the average ammont of power (mW) generated by the solar panel)
        # The more power generated by the solar panel the lower the price, and vise versa.
        mW_price = 10 / average_PANEL_mW # 
        
        # Calculate IOTA payment based on current mW price and average power consumption
        # Discard any decimals
        pay_value = int((average_LED_mW * pay_frequency)*mW_price)
               
        # Send IOTA payment
        pay(pay_value)
        
        # Reset and prepare for next payment round
        accumulated_LED_mW = 0.0
        accumulated_PANEL_mW = 0.0
        pay_counter = 0
       

    # Get current LED power consumption
    current_LED_mW = get_current_LED_mW()
    
    # Add current LED power consumption to accumulated LED power consumption 
    accumulated_LED_mW = accumulated_LED_mW + current_LED_mW
    
    # Get current solar panel power generation
    current_PANEL_mW = get_current_PANEL_mW()
    
    # Add current solar panel power generation to accumulated solar panel power generation 
    accumulated_PANEL_mW = accumulated_PANEL_mW + current_PANEL_mW
    
    # Increase pay counter
    pay_counter = pay_counter +1
    
    # Wait for one second before taking a new reading
    time.sleep(1)