Are the benefits worth the cost of installing solar lights

We have solar panels on our roof for general running of the house electricity. We have just recently refurbished our kitchen and hence put in new whiz bang lighting. Trish was speaking to a friend at work who said that just installed new solar lights. A minimal cost be $300 for fitting one light. I personally do not think the cost of installing one of these lights would give you the benefits for us.

$300 per light, that means that to save on electricity costs, one would have to fun the lights for at least 120 000hrs (assuming 10W light and 0.25c/kWh for mains power) over its life to get ones money back. I have not heard of any lights lasting 120 000 hours so economically it would not be justifiable. LED have a design life up to 50 000 hours if they are installed correctly (e.g. not subject to high temperatures).

I would suggest that they would only become viable if for example, they were installed shed or out building where the cost of connecting main power is prohibitive.

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@Ian_Mac by ‘solar lights’ do you mean the reflective solar tubes than beam sunlight into your house through a tube in the roof cavity? They can cost up to $1000 and for lighting they don’t represent good value for money IMO, although they certainly can brighten up a room that is a bit gloomy if you dont want to use any electricity. If you already have PV panels, then there is a wide range of good quality LED lighting that will cost under $300, even for very high power output.

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Hi Gordon, I assumed this was the sort @Ian_Mac was talking about…Interior solar lights example

Ahh I see, thanks.

If Ian_Mac already has PV panels, then I think installing LED lamps in existing fittings would make much more sense than the linked expensive lighting system. Small panels such as the 20W panel in that kit are much more expensive ($/watt) than large panels used in grid-connected systems, and the 10AH 12V Lead-acid battery would not last all that long if used into deep discharge each night.

As you suggested above, it could never pay for itself, and the added complexity with controllers and batteries mean more maintenance and expense over time.

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Agree @gordon. The money left over from LEDs could also be spent on buying say 10% green power from one’s electricity retailer, if the original solar light idea was an ethical one.

We have been changing our CFL lights to LEDs when the CFLs fail…and have been impressed with the LED bulbs/nature of the light…and good LED lights are quite affordable and have short paybacks (if converting from conventional lighting).

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Thank you for your advice and we have overcome the situation by not installing solar reflective tubes.

Thank you for your advice and we have not installing solar reflective tubes but we installed lighting recommended by our kitchen installing group. They wanted us to think highly of them for future recommendations.