Diesel expenditure eroding profits

Calculations provide a clear illustration of the potential cost savings that can be achieved through the integration of solar systems with generators.

Let’s break down the example:

1.   Generator Capacity: 100kVA

2.   Hours of Load Shedding per Week: 10 hours

3.   Price of Diesel: R23.41/liter

With this information, let’s calculate the annual generator fuel costs without integration:

Annual fuel consumption = (Fuel consumption per hour) * (Hours of load shedding per week) * (Weeks per year) Fuel consumption per hour = (Generator capacity in kW) * (Diesel consumption rate in liters per kWh) Weeks per year = 52 weeks

Given the generator capacity is 100kVA, we’ll need to convert kVA to kW since the diesel consumption rate is usually provided in liters per kWh.

1.   Convert kVA to kW: 100kVA = 100kW

2.   Calculate fuel consumption per hour: Since the generator runs at 100% capacity during load shedding, the fuel consumption per hour is the generator’s fuel consumption rate at full load.

3.   Calculate annual fuel costs using the fuel consumption per hour and the price of diesel.

Let’s do the calculations:

Fuel consumption per hour = 100kW * (Diesel consumption rate in liters per kWh) Let’s assume a typical diesel consumption rate of 0.25 liters per kWh (this may vary based on generator efficiency).Fuel consumption per hour = 100kW * 0.25 liters/kWh = 25 liters/hour

Annual fuel consumption = 25 liters/hour * 10 hours/week * 52 weeks/year = 13,000 liters/year

Annual fuel costs = 13,000 liters/year * R23.41/liter ≈ R303,930 per year

Now, let’s calculate the potential savings with generator integration:

With integration, the generator only operates at 30-40% of its capacity during solar generation periods. Let’s assume it operates at 40% for this example.

Generator capacity during integration = 100kW * 40% = 40kW

Fuel consumption per hour during integration = 40kW * 0.25 liters/kWh = 10 liters/hour

Annual fuel consumption during integration = 10 liters/hour * 10 hours/week * 52 weeks/year = 5,200 liters/year

Annual fuel costs during integration = 5,200 liters/year * R23.41/liter ≈ R121,672 per year

This results in potential savings of approximately R182,258 per year, which represents a significant reduction of around 60% in generator fuel costs compared to running the generator at full capacity during load shedding without integration.

These calculations demonstrate the substantial cost savings achievable through integrating solar systems with generators, making it a compelling solution for businesses looking to mitigate the impact profit erosion by load shedding on their operations.