Georgetown Secondary

ContentsChapter 1 - Executive Summary...................................................................................................................3

Chapter 2 - Facility Description and Findings...............................................................................................4

Analysis of consumption and load per end use.......................................................................................5

Benchmark Analysis.................................................................................................................................6

Chapter 3 - Energy Efficiency Measures......................................................................................................7

Lights.......................................................................................................................................................7

Air Conditioning.......................................................................................................................................7

Refrigeration............................................................................................................................................8

Roof Radiation.........................................................................................................................................8

Renewable Energy Opportunities............................................................................................................8

Energy Efficiency Measures with a Payback Period of less than 1 year...................................................9

Recommended Investment Package.....................................................................................................10

Chapter 1 - Executive Summary

There are 500 people using this facility.

A summary table of results of recommended energy conservation measures is shown below.

Significant parameter Value

Electricity Reduction per Annum 51,851 kWh 51,851 kWh

Load saving 54 kVA

Annual Cost Savings (EC$)2 $72,119

Percent Energy Reduction3 57 %

Energy Measures Project Cost (EC$)2 $174,109

Simple Payback Period 3.1 years

Principal electricity end uses in the facility are:

- Lights for 33 %- Air condition for 32%- Computers for 28%

Therefore, it is important that strict attention be paid to ensure operation and maintenance for optimum performance of the systems in use.

Based on the energy audit results, we recommend two types of the Energy efficiency (EE) measures to be implemented in order to reduce energy costs, and enhance occupant comfort:

1. “Low cost” EE measures with a payback period of less than one (1) year from energy and maintenance savings. These are advice about the way of reducing the energy consumed with simple maintenance measures and behavior.

2. EE measures with longer payback period and more significant investment cost. These measures require some investment on critical consuming points, as replacing non-efficient equipment by new ones. In addition, we suggest a few measures to reduce the energy consumption by productive installations.

1 It is important to note that the walk-through-audit aims at identifying general efficiency opportunities and does not provide extensive electrical measurements as a detailed or comprehensive energy audit. Hence, it is recommended that additional measurements and analysis be carried out before any major modification or retrofit.2 Exchange rate: 1 US$ = 2.70 EC$3 The Percent Energy Reduction is only based on the “Recommended Investment Package” which does not include the “Low cost” EE measure and the “Other Projects Under Consideration”

Chapter 2 - Facility Description and Findings

Georgetown Secondary School is located in Georgetown, St Vincent. 800 persons are present in this building.The facility comprises a combination of two and single storey buildings made of steel reinforced concrete. The roof is a combination of pitched and flat corrugated alu-steel sheets, well supported by rigid steel structure. The facility shows signs of severe corrosive deterioration due to the salty sea water environment. Generally it does not appear to be well maintained. The facility was built around 1995.

Figure 1: Footprint Georgetown Secondary

The total area calculated is 4,461 m² and 334 m² are under air conditioning.

The total electricity consumption is 45,600 KWH for year 2009.

Analysis of consumption and load per end useThe breakdown of relative energy demand (kVA), consumption (kWh), and costs, of the electrical end uses are presented hereafter. Based on the energy audit, a breakdown of the annual electricity consumption has been reconstituted and is presented in Table 1 and Figure 2.

Table 1: Estimated Annual Electricity End Use

Estimated Annual Cost

Description Installed (kVA) Annual kWh US$ EC$Lights 39 35,401 12,036 32 498

Computers 16 30,792 10,469 28 267

Resistive 3 390 133 358

Equipment 4 832 283 764

Refrigeration 2.6 6,263 2,129 5 749

Air Conditioning 33 34,842 11,846 31 985

Total 97.14 108,519 $36,896.46 $99 620

This diagram reveals that Lighting, air conditioning, computers and equipment are the primary electrical end uses, with respectively 33%, 32%, and 28% of total annual electricity consumption.

Figure 2: Breakdown of Estimated Electricity (kWh/year) End Use

Benchmark AnalysisTable 2 summarizes the historical energy consumption per month and indicates that the average monthly energy use compared to the recommended benchmark is low. This results in a consumption decrease below recommended benchmark. Since we are confident in our input data and our energy model has already been proven we believe there are multiple meters on this site or the meter is faulty. Based on the current use and type of equipment at this facility there is a significant opportunity for energy efficiency improvement, and every effort should be made to implement the optimization measures recommended in this report.

Table 3 indicates that the historical energy consumption and the estimated consumption based on an engineered estimate of end use do have a significant variation i.e. -138%..

Chapter 3 - Energy Efficiency Measures

LightsWe recommend replacing the fluorescent T12 tubes of with LED, 17W tubes to improve the lighting efficiency.

As an option T8s can be used but we believe there is strong need to significantly reduce the power demand in spite of LEDs initial higher capital outlay.

LEDs also offer a much longer lifetime and almost no maintenance which makes it very attractive for a school environment.

High power security lights will also be replaced with LED floodlights. We also advise turning off the exterior lights of the building, lights in luminous rooms and installing occupancy sensor switches in intermittently occupied offices.

Air ConditioningWe recommend increasing space cooling thermostat settings to 25º C and replacing the existing inefficient split AC units with new ones rated at minimum energy efficiency ratio (EER) 13 or Coefficient of Performance (COP) of 3.7.

Figure 3: T12 Fixtures at Georgetown Secondary

Figure 4: Typical LED replacement bulb

RefrigerationTo optimize refrigeration system efficiency, we recommend that HCFC and HFC refrigerants should be replaced with Hydrocarbon (HC) Refrigerants. Refrigeration is insignificant in this facility.

Roof RadiationThere is important roof radiation coming from the roof which needs to be reduced with proper insulation which will significantly contribute to lowering AC load in the staff room and other cooled areas on the top floors.

Renewable Energy OpportunitiesThe following measures have to be considered but are not recommended at this time, because of their long payback period.

1. Installation of solar photovoltaic (PV). There is a large central flat reinforced sheet section of this roof makes it ideal for solar PV. The economics with an estimated payback period of 7.5 years is still not very attractive in the short term. Energy efficiency improvements in lighting and air conditioning should first be applied to enable reducing the investment cost for PV installation. This should be reviewed based on PV price reduction and/or availability of funding.

Electricity for daytime lighting, computers could be offset by a 30-kW solar PV/wind hybrid system.

Energy Efficiency Measures with a Payback Period of less than 1 yearWe recommend some immediate measures that would make a positive impact on the energy cost reduction effort, and enhance occupant comfort without major capital expense, with a payback period of less than one (1) year from energy and maintenance savings:

General

1. The Principal to immediately establish an energy management programme which means obtaining monthly energy consumption and billing, sensitizing all individuals using the facility to adopt better energy efficient practices like turning off lights and fans etc.

2. Reduce “phantom loads” by switching off all office equipment step-down transformers at the end of the business day.

Lighting

3. Turn off the lights and fans in rooms, and corridors when not occupied..

4. Disassemble and clean all lighting diffusers.

5. Measure lighting intensity and reduce fluorescent tube quantity where practical.

6. Install occupancy sensor switches in intermittently occupied offices, staff changing rooms and washrooms (US$100.00 each).

7. High power floodlights burn a significant amount of power even when the bulbs are blown as a result of the onboard ballast, At this facility approximately half he outdoor floodlights are not working but still burning a huge % of electricity. The circuits need to be disengaged if the lights will not be put into use for an extended time.

Refrigeration

8. Retrofit all refrigeration unit compressors with high efficiency (Frigitech) lubricant (US$50.00/hp/compressor)

9. De-scale evaporative cooled condensers utilizing specialized chemicals.

Air Conditioning – Service all split systems and window units

10. Increase space cooling thermostat settings to 25º C, a setting of 18º C was observed in the directors’ office on the auditor’s visit and it was very cold.

11. De-scale related evaporative cooled condensers utilizing specialized chemicals.

12. Replace the existing inefficient mini-split AC units with new ones rated at minimum energy efficiency ratio (EER) 13 or Coefficient of Performance (COP) of 3.7.

13. Close doors to outside building and keep cooled air in building

Recommended Investment PackageThe table 4 summarizes all the effective measures which require a payback period of more than one year. The first part, called “Recommended Investment Package”, relates to the most effective measures. The second part, called “Other Projects under Consideration” is a few optional suggestions.

Figure 5: Potential Effects of Energy Optimization Projects