Tag Archives: industrial

FAURECIA Energy Efficient Lighting Upgrade

Induction Lighting

Grey Green has been awarded a contract for a major lighting upgrade at Faurecia’s Cape Town operation. The scope of the project includes financing, supply and installation of the new lights, before and after lux level drawings, as well as a 3 year maintenance program. This project shall save our client approximately R 2.5 M over 3 years and is expected to be completed by end June 2014.

Energy Efficient LEDs for Vector Logistics Cold Rooms

LED lights are a very good choice for cold room warehouses. After a very rigorous trial phase, Rick du Toit, regional plant engineer at Vector Logistics in Cape Town, decided on a LED light supplied locally by Lighting Revolution. The trial period involved testing different strength lamps with a various range of reflectors.

The light that was finally chosen was a 130W tunnel lamp, made up of two chips with separate cone reflectors at 120 degrees. These lights give a very even spread of light for warehouses with high ceilings of up to 13 meters.

The project was managed by Grey Green (as the ESCo), who made use of the Eskom Standard Offer Rebate Programme.  The project has been completed and the post assessment report has been published by the independent ESKOM appointed Monitoring and Verification team (M&V).

A summary of the changes that took place is given below:

  • 130 x LED Tunnel lamps were installed (130W each including electronic driver)
  • The lights are replacing 107 x 400W metal halide lamps (low bay fittings) and 23 x 1000W halogen wedge lamps
  • 27 of these lights are in areas where the ceiling height is 5 meters or less
  • 103 are in areas where the ceiling heights are between 11 – 13 meters high
  • Approximately half the lights are in cold rooms at between -4 and -6°C, the other half are in -25°C freezer rooms

Part of the project involved trialling the lights extensively, including switching tests as well as testing the lamp in the freezer rooms, which is the more severe operating climate. Based on the trial results the project went ahead using the tunnel lamp fitting from Lighting Revolution. The implementation was not without its challenges because of working in freezing room temperatures, but the installation team (FLASH Electrical) rose to the occasion. All battery operated equipment (lifting devices, drills and flash light) used needed to be warmed intermittently in order for it to operate correctly. This led to slight delays in implementation schedule, but overall the project went extremely well.  The results, measured in terms of increased lux levels on the plant floor as well as substantial energy savings, were quite incredible.

The M&V baseline report revealed that the metal halide lights consume on average 400W and the halogens 1080W. This fact may seem obvious but depending on the type of ballast and site’s average voltage the rated power drawn by a light fitting can vary by up to 50W or 10%.  The average lux within the plant rooms was between 70 – 100 lux before the implementation (due to degradation of the lux levels as the lights age).

After the post assessment measurements it was revealed that the LEDs performed better than expected in the cold environment. The 130W rated fittings on average drew 126W. The additional savings can be attributed to the cold climate within the cold rooms which helps dissipate heat from the fittings which is a typical weakness of LED lights. The average lux levels post the implementation was 180 lux even in the areas with 13 metre high ceilings.

The lights will thus save 51kW, equivalent to 447MWh per annum. This at current tariffs is equivalent to R 360 000 per annum. The Eskom rebates for LED interventions on the SOP programme are 0.55 c/kWh saved during the SOP qualifying times. This has resulted in the rebate subsidizing approximately 45% of total project costs!

The LEDs have IEC certification, and come with 50 000 hour or 3 year warranty. The indirect benefit of the LED lights is that they also have far less ballast losses and because of their lower operating temperatures there will be less heat dissipated into the cold room which should in theory lead to a slight saving in refrigeration load.

The project has served to demonstrate that using the correct light for a particular environment can be very effective leading to increased lighting levels as well as cost savings.

Gabriel- Industrial Energy Efficiency Interventions

The case study presented here is based on an automotive parts manufacturing plant in Western Cape. The high level energy auditing process is shown below in various possible stages. The figure also highlights the potential for increasing savings that can be achieved at each stage. Subsequent stages can usually be partially funded by the savings achieved in the predecessor stage so the capital outlay is kept to minimum and within our client’s budget while creating a positive savings spiral. The offering can also be tailored to include only the selected stages that meet the client’s requirements.

EE Spiral

After the ESCO (Grey Green) conducted an on-risk diagnostic energy audit at the client’s plant during 2012, multiple energy saving initiatives were identified and recommended in detailed business cases. The client preferred a shared-savings business model in which the interventions were financed by the ESCO and then paid for as a percentage of the verified savings over a fixed and agreed period. These payments occur only after the project installations have been completed and as savings are realized. The client therefore takes very little upfront risk, does not need to wait for and/or go through any major CAPEX approvals or budgeting cycles and has a positive cash flow from day one.
The first three interventions that were implemented were at absolutely no upfront cost to the client. The client is currently saving an estimate of 1.5 million kWh hours per year. The average annual demand savings thus far are 170 kW. The actual cost to the client thus far has been approximately R2600/kW saved, all paid for from their monthly savings. The high bay lighting retrofit utilized the ESKOM Standard Offer Programme rebates while the fluorescent lighting retrofit utilized the ESKOM Standard Product Programme rebates. The compressed air system optimization is currently in progress. The total savings are shown by intervention type in the diagram below. The interventions are provided with performance guarantees, pre- and post-installation monitoring as well as a maintenance plan which ensures that all savings are sustained.

Pie-chart of Savings Breakdown

Future interventions planned at this plant include the introduction of Variable Speed Drives (VSDs) on cooling towers, intelligent control of extraction fans, motion sensors for lights, efficient heating and cooling systems for process baths and waste heat recovery. Once these interventions have been completed, there is also the potential for embedded generation using a grid-tied rooftop solar PV system to further reduce consumption. The client shall also benefit from various manufacturing sector incentives such as the Manufacturing Competitiveness Enhancement Programme (MCEP) for assistance with funding these interventions in addition to already having accessed the ESKOM rebates to subsidize their projects. Grey Green has now also been requested to facilitate similar intervention projects at the other divisions within the entire group of companies.
Whilst all the interventions result in substantial savings and reduced demand charges for the client, they also improve the competitiveness of the client’s core business, reduce their carbon footprint and reduce any potential carbon tax burden.

Feasibility of Solar Thermal Collectors to Supply Industrial Process Heat

This was a similar study to the water heating study however this was focuses on the feasibility of providing process heat for the food and beverage industry. The focus of this study was to establish the potential for solar thermal energy in the Western Cape food and beverage industry. This was a two part study – the first was establishing the potential size of the energy consumption in this sector, on a provincial level, and estimating with reasonable assumptions what quantity could be supplied by solar energy. The second was to model solar water heating systems, using actual processes used in three local manufacturing plants, to establish the cost at which the various solar water heating technologies could be implemented at and how much energy these systems could supply.