LED bulbs are now available at a similar price as the older compact fluorescent low-energy bulbs – typically £3-£4 for branded bulbs when bought in multipacks.  This means that payback times are of the matter of a few months rather than years.  

To illustrate the running costs here is a simple calculation:

Assumptions

Standard GU10 halogen 50W bulb £2

Philips 4.5W LED GU10 (equivalent output to 50W halogen) £3.50

Electricity cost:   12p/kWh

LED lifespan:   15,000 hours (equivalent to around 15 years)

Halogen bulb lifespan 2,000 hours (equivalent to around 2 years)

Typical use: 3 hours per day

 

Annual running cost of LED bulb: 0.0045kW x 0.12p/kWh x 3 hours x 365 days = £0.59

Annual running cost of halogen bulb: 0.050kW x 0.12p/kWh x 3 hours x 365 days = £6.57

Annual savings = £6.57-£0.59 = £5.98

 

The additional £1.50 cost of purchase is therefore paid back in approximately 3 months.

 

Attachments

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LED Payback.pdf91.61 KB