Does your factory power off each machine at the end of a shift? If it doesn’t, and there’s no operational reason not to, then you’re likely to be wasting energy and money that could be easily saved by powering the machines down.
This article looks at the financial, operational and environmental reasons why manufacturers should, wherever possible turn off their machines and includes a use case showing the cost savings a manufacturer could achieve by powering down their 14 CNC machines when not in use.
Powering off idle machines can offer several benefits for manufacturers
Energy Conservation:
One of the primary reasons for turning machines off when not in use is to conserve energy. Industrial machines often consume a significant amount of electricity, and keeping them running when they're not actively producing can result in unnecessary energy costs. Turning machines off during periods of inactivity helps reduce overall energy consumption and lowers electricity bills.
Cost Savings:
Energy is a major operational cost for manufacturers. By turning machines off when they're not needed, manufacturers can save on electricity expenses, contributing to overall cost savings. This is particularly important for businesses looking to improve their bottom line and remain competitive in the market.
Equipment Lifespan:
Continuous operation can contribute to wear and tear on machinery. Turning machines off during idle periods gives the equipment a break, potentially extending its lifespan. When properly powering off (down) any machine it is important to ensure it is done as per the manufacturer's recommendations, if done incorrectly it could cause unforeseen and costly damage to the machine.
Environmental Impact:
Energy consumption is closely linked to environmental impact. By minimising energy usage, manufacturers can contribute to environmental sustainability and reduce their carbon footprint. This can be an important factor for companies looking to align with environmental regulations, meet sustainability goals, or appeal to environmentally conscious consumers.
Compliance with Regulations:
In some regions, there are regulations and standards in place to promote energy efficiency and reduce environmental impact. Turning off machines during idle times can help manufacturers comply with these regulations and avoid potential fines or penalties.
Operational Efficiency:
Powering off machines when not in use is part of good operational management. It allows for better control of resources and ensures that production resources are used efficiently. This practice can be integrated into broader strategies for improving operational efficiency and optimising resource utilisation.
While there may be cases where continuous operation is necessary for specific manufacturing processes, overall, turning machines off during idle periods is a sound strategy for resource conservation, cost savings, and environmental responsibility.
Understanding the energy consumption of your machines and estimating the cost
The energy consumption of a machine can vary widely depending on factors such as its type, size, efficiency, and the nature of its operations. For illustration purposes, here is a commonly used, simplified calculation:
Power Rating (Watts or Kilowatts): The power rating of a machine, typically measured in watts (W) or kilowatts (kW), indicates how much electrical power it consumes when in operation. For example, a machine with a power rating of 1,000 watts consumes 1 kilowatt-hour (kWh) of electricity for every hour it operates.
Duration of Operation: The number of hours a machine is left on during a day is a crucial factor. If you know the power rating of the machine and the number of hours it operates, you can calculate the daily energy consumption in kilowatt-hours (kWh).
Electricity Cost: The cost of electricity varies depending on location and other factors. Electricity is typically billed in kilowatt-hours, and the cost per kWh can be obtained from the utility provider.
A commonly used formula to calculate the daily energy cost is:
Energy Cost (in currency) = Power Rating (in kW) × Hours of Operation × Cost per kWh
For example, if a machine has a power rating of 2 kW, operates for 8 hours a day, and the cost of electricity is £0.10 per kWh:
Energy Cost = 2kW × 8hours × £0.10/kWh = £1.60
Please keep in mind that we have used a simplified calculation for this example, and the actual energy cost may vary based on factors such as fluctuations in electricity rates, the efficiency and age of the machine, and any standby power consumption when the machine is not actively in use.
To get an accurate estimate, you may want to consult the machine's specifications or speak with the manufacturer to determine its power consumption characteristics. Another option often used by manufacturers is to get an energy audit done by a professional who can provide more precise insights into the energy usage of specific machines within a manufacturing facility.
Using smart technology to monitor energy usage
Additionally, there are several energy monitoring technologies available on the market that can accurately measure the energy consumption of machines. One solution is FourJaw’s machine monitoring platform, which features energy monitoring capability in addition to the productivity data insight it captures. Using such technology as FourJaw’s, manufacturers can:
- Understand the cost of energy used by machine, cell, production line or factory.
- Understand whether energy is wasted on downtime or consumed by productive work.
- Understand carbon footprint by machine to support sustainable manufacturing initiatives.
How does FourJaw calculate energy consumption, efficiency, carbon footprint and cost?
Single Phase:
P = pf × I × V / 1000
In this formula, the amount of power - P (in kW) is equal to the power factor of the load (pf) multiplied by the phase current measured in Amps (A), multiplied by the voltage between the phase and neutral (V), and divided by 1000.
3 Phase
P (kW)= √3 × pf × I × V /1000
The power - P (in kW) equals the square root of three (√3) multiplied by the power factor (pf) multiplied by the current in Amps (A), multiplied by the Phase voltage (V) divided by 1000.
To calculate the cost FourJaw multiples the power used by the cost per kWh given on the settings page.
To calculate the carbon footprint FourJaw multiplies the power used by the kilograms of carbon equivalent per kWh given on the settings page. This is defaulted to the UK government-approved value.
Use Case: Saving more than £17K per annum in wasted energy costs by powering off machines when ‘Off shift’
We recently demonstrated our Energy monitoring feature to a customer who had originally installed FourJaw primarily to understand and improve their manufacturing efficiency by monitoring each machine's productivity data.
Using the energy usage data captured by FourJaw the manufacturer was able to see the cost of energy being used across all 14 of their CNC machines during ‘On Shift’ and ‘Off Shift’ periods.
The data showed that if the machines were fully powered off when ‘Off Shift’ then they could save around £17,500 per annum, based on the price per kWh of 0.25 (GBP) and assuming that the shifts will follow the same pattern over 7 days for 52 weeks
Costs shown in GBP. Calculations based on a cost Per KwH of 0.25 (GBP). Data is based on typical shift patterns. Excluding any over-time shifts
The manufacturer is now able to understand the true cost of wasted energy and is making informed changes to the way machines are powered up and off for shifts. In addition to the financial benefit this has on their factory, the manufacturer is also able to understand and evidence their carbon footprint and measure the reduction off the back of the changes they implement.
