The sale of standard 'pear-shaped' halogen lightbulbs in the European Union is being formally phased out.

From Saturday, retail outlets across Ireland and EU member states can only order LED bulbs, which are more energy efficient.

Household LED bulbs on average cost €2 per year to run and can last up to 20 years.

The ban covers "energy intensive and inefficient halogen lightbulbs".

The changes relate to standard halogen bulbs (mainly the pear-shaped ones) with non-directional light.

But it does not cover special types like those used in desk lamps and floodlights.

The new measures will also not apply to products that are already on the shelves in shops, but only to new products produced in or imported to the EU.

Originally decided in 2009, the new rules were reconfirmed in 2015 - but their introduction was deferred until September 2018 to ensure sufficient alternatives would be available.

Image: European Commission

A study in 2013 estimated that switching from an average halogen lamp to an energy efficient LED would save at least €115 in the lifetime of the bulb, and pay back its cost in 12 to 18 months.

The same study estimated that, by implementing the rules at EU level, the changes would provide annual savings equivalent to the electricity consumption of Portugal over five years.

These savings correspond to a reduction of 3.4 million tonnes of CO2 emissions every year.

The EU says the changes will also mean a significant reduction in waste, as consumers will use considerably fewer light bulbs every year - and the new LED bulbs are recyclable.

The EU Commission says: "By substituting a halogen lamp with an LED, you could save up to €100 over the product's lifetime of around 20 years.

"Energy efficient lighting could save enough energy to power 11 million households for one year and avoid the emission of 12 million tonnes of CO2 in Europe."

Emergency lighting and some LEDs - designed for very specific uses and sold in very small quantities - are excluded from the regulations.