Energy Savings Through Efficient Lighting Solution
Introduction
Managing electricity costs is a critical concern for commercial buildings, particularly those with extended operational hours. One effective method to address this challenge is through the optimisation of lighting systems, specifically by implementing energy-efficient solutions. This case study demonstrates one way our Company could make you savings by exploring the opening times of a warehouse and creating an energy-saving strategy, focusing on the use of existing lights for improved efficiency.
Understanding the Existing Scenario
This warehouse was operating for 127 hours per week, but the lights were fully illuminated for 168 hours per week; therefore electricity consumption to power these lights was being used at an additional and wasteful 41 hours per week. By analysing the operational hours, we were able to estimate the energy consumption for lighting systems and identify opportunities for cost reduction.
Lighting Requirements
For a warehouse of this size, lighting is a significant contributor to overall electricity usage. Conventional lighting systems, such as halogen or incandescent bulbs, often consume excessive energy, leading to unnecessary costs. The operational hours provide a framework for calculating existing energy use and adopting more cost-efficient setup to reduce energy bills if even before an LED upgrade is considered, which if also invested in, could reduce costs even further.
Calculating Energy Consumption
To assess potential savings, it is essential to calculate the current energy usage and compare it with the projected consumption of more efficient lighting solutions like automated timers or manual override options.
Step 1: Current Energy Consumption
To calculate current energy consumption, we researched the kw usage of a single light fitting in the warehouse, by retrieving the exact specification of the light. We could then multiply this by time e.g. we multiplied the kw by the number of hours in excess these lights were in operation i.e. 41 hours and then this gave us a kwh figure for each light fitting.
The kwh could then be multipled by the cost in pence per kwh from the energy company to work out the costs to run the existing lighting.
Real-life example:
The lights were being run for 24 hours a day, which is 168 hours per week, meaning that the lights were lit for 41additional hours per week than actually needed.
Spec of existing lights = 383w OR 0.383kw per light fitting
0.383kw x 41 hours = 15.703kwh
The price per kilowatt hour had increased from 0.16p in 2021 to 0.38p in 2022.
15.703 x 0.38p = £5.97 per fitting per 41 hours/1 week
£5.97 x 292 light fittings = £1743.24 per 41 hours/1 week
£1743.24 x 52 weeks = £90,648.48, which breaks down to £7554.04 per month.
If the lights could be turned off during those 41 non-operational hours, £90,648.48 was what we could save the client.
Step 2: Making improvements to achieve this saving
In the case above, installed and implemented alternative controls to allow for a local 2 position selector switch per main section of lights which enabled an on/off function, to give more control over the system as all the lights were permanently on. In order to implement these controls, panels housing contactors were installed in close proximity to the distribution board serving the lighting. The circuits were intercepted and wired through these contactors and switches installed in the main office which would operate the contactors.
For any spaces that are running halogen or incandescent bulbs, the above calculations could be carried out on an LED alternative which would use less wattage and a direct price comparison could be seen. This could then be offset against the price of an LED installation upgrade to provide the client with a timeframe of how long it would take for them to see a return on their investment
At each stage, it is important that the energy prices are accurate i.e. provided by that client’s energy provider in order to be able to calculate accurate costs and savings for the client.
Implementation Recommendations
To achieve maximum efficiency, the following steps are recommended:
- Install efficient LED lighting: Upgrade the existing lighting system to LED-based lights for immediate energy savings.
- Implement motion sensors: Reduce unnecessary lighting usage by installing motion-activated sensors in low-traffic areas.
- Implement manual overrides as an option so the client has the ability to save on energy consumption further if possible.
- Regular maintenance: Ensure all lighting fixtures are properly maintained to avoid energy wastage due to malfunction.
Conclusion
This case study demonstrates that by analysing operational hours and replacing conventional lighting with energy-efficient solutions, a commercial building such as a warehouse or office can significantly reduce its electricity costs. With projected annual savings, investments in efficient lighting systems not only lower operational expenses but also contribute to sustainability goals. This offers a practical and effective solution for businesses committed to energy optimisation.
