Sut I Gyfrifo Cost Oes Bywyd Golau Mast Uchel

1. Cyflwyniad

Systemau goleuo mast uchelmae'n hanfodol ar gyfer ardaloedd mawr fel maes awyr, porthladdoedd môr, cyfnewidfeydd priffyrdd, a chymoedd chwaraeon. Wrth ddewis neu uwchraddio'r systemau hyn, mae'r pris prynu cychwynnol yn aml yn ystyriaeth bwysicaf. Fodd bynnag, gall y safbwynt cul hwn fod yn gamarweiniol. Mae ymchwil yn dangos bod y taliad cychwynnol yn cyfrif yn nodweddiadol am tua 20% yn unig o'r cost cyfan dros oes y system, tra bod 80% yn ddyledus i weithredu a chynnal a chadw. Felly, mae dadansoddiad Cost Bywyd-Cylch (LCC) yn hanfodol er mwyn gwneud penderfyniadau economaidd iawn.

Mae'r erthygl hon yn esbonio sut i gyfrifo LCC ar gyfer lampau mast uchel, yn cymharu lampau sodiwm pwysedd uchel (HPS) traddodiadol â dewisiadau LED modern, ac yn darparu methodoleg cam-wrth-gam gyda enghreifftiau o'r byd go iawn.

 

 

2. Cydrannau bywyd-Cost Cyrchred Bywyd

Mae cyfanswm CCL system goleuo mast uchel yn cynnwys tri phrif gategori cost:

2.1 Cost Cychwynnol Buddsoddi

Pris prynnu goleuadau, polion lampau, sylfeini, ceblau, a chyfarpar cynorthwyol.

Llafur gosod a chomisiynu.

Enghraifft: Mae lliain HPS 400 W yn costio tua $200, tra bod ffitr LED cyfatebol o ran disgleirdeb yn costio $300. Mae gan y LED gost gyntaf uwch ond mae'n cynnig arbedion hirdymor.

2.2 Energy Operating Cost

This is the largest recurring expense. It is calculated as:

Annual energy cost=Total power (kW) × Annual operating hours × Electricity tariff (¥/kWh)

For instance, at Dali Airport, replacing one HPS high mast lamp with LED saved 7.5 kWh per hour of operation. With 10 hours of daily use, annual savings reached 27,375 kWh, equivalent to about $1800 in electricity.

2.3 Maintenance and Replacement Cost

This includes lamp replacement, driver/power supply replacement, routine inspections, and fault repairs. Significant differences exist between technologies:

LED fixtures: Annual maintenance ~$50–$70 per mast; total fixture life >=5 years; annual maintenance only about $6 per luminaire. In one project, the 5-year operating cost of LED was $12000 less than that of HPS.

 

 

3. LCC Calculation Formula

LCC=I+∑t=0nEt+Mt(1+r)tLCC=I+t=0∑n(1+r)tEt+Mt​​

I=initial investment (at t=0)

Eₜ=annual energy cost in year t

Mₜ=annual maintenance cost in year t

r=real discount rate (e.g., 5% per year)

n=analysis period (typically 10–20 years, matching the system's design life)

Determine the analysis period (usually 10 years for high mast lighting).

Collect annual energy consumption and maintenance data for each alternative.

Apply the discount factor to each year's costs and sum them.

Add the initial investment – this gives the total present-value LCC.

Tip: If costs are relatively stable year over year, you can simplify by using the annuity formula, but the step-wise approach is more accurate when replacement cycles vary.

4. Step-by-Step Calculation Example(Case in China)

Assume a 10-year analysis period, a discount rate of 5%, and the following data for one LED high mast:

Initial investment (I)=¥25,000 (fixture, pole, installation)

Annual energy cost (E)=¥1,478 (constant)

Annual maintenance (M)=¥50 (constant)

LCC=25000+∑t=1101478+50(1.05)tLCC=25000+t=1∑10​(1.05)t1478+50​

The sum of discounted annual costs (using a financial calculator or spreadsheet) is approximately ¥12,100. Adding the initial investment gives a total LCC of about ¥37,100.

For the HPS alternative (I=¥20,000, E=¥3,285, M=¥300), the discounted annual sum ≈ ¥27,500, plus initial ¥20,000=¥47,500. LED is ¥10,400 cheaper over 10 years despite a higher first cost.

5. Important Considerations

Define the analysis period – use the design life of the longest-lasting component (often the high mast lamp pole or the LED driver).

Apply discounting – always convert future expenses to present value using a realistic discount rate.

Include extraordinary events – lightning strikes, pole knockdowns, or major failures should be estimated separately and added if probabilistic data are available.

Regional variations – electricity prices, labour rates, and ambient temperature (affecting LED heat-sink performance) can significantly affect results, so adjust inputs accordingly.

Sensitivity analysis – test how changes in electricity price or discount rate affect the ranking – this helps manage uncertainty.

6. Conclusion

Life-cycle cost analysis is an indispensable tool for . Although LED luminaires have higher upfront costs, their superior energy efficiency and lower maintenance requirements deliver substantial savings over the system's lifetime. In most cases, the payback period for LED retrofits is 2 to 4 years, and the total LCC advantage is clear.

For airport aprons, port terminals, and large interchanges, an LCC study should be mandatory before any procurement or refurbishment. By following the formula and steps outlined above, facility managers can make transparent, data-driven decisions that optimise both financial and operational performance.

7. Suggested Figures for Your Word Document

To enhance readability, please insert the following figures (you can create them using Excel or similar tools, or source from open-access reports):

Figure 1 – LCC cost breakdown (pie chart) – show typical percentages: e.g., Initial cost 20%, Energy 60%, Maintenance 20% for HPS; and Initial 25%, Energy 45%, Maintenance 30% for LED (adjust based on your data).

Figure 2 – Annual cost comparison (bar chart) – compare HPS vs. LED for each year, highlighting cumulative savings.

Figure 3 – Discounted cash flow over 10 years (line graph) – plot cumulative present-value costs for both alternatives.