What is the Equivalent Wattage for Energy Saving Bulbs?

What is the equivalent wattage for lamps that save energy?

Modern energy efficient/saving bulbs are almost always LEDs, which use up to 90% less electricity than traditional incandescent bulbs. They require much lower wattage to produce the same brightness, making them the most efficient and cost-effective option.

While older compact fluorescent lamps (CFLs) and halogen energy savers were once common, these are now largely phased out in favour of LEDs, which are longer-lasting, more efficient, and available in a wide range of shapes and fittings.

Below is a guide to typical LED equivalents for traditional incandescent bulbs.

Traditional Bulb vs LED Equivalent

Traditional Incandescent Bulb LED Equivalent Approx. Light Output (Lumens)
25W 2–4W 200–300 lm
40W 4–6W 400–500 lm
60W 7–10W 700–900 lm
100W 12–15W 1,200–1,500 lm

LEDs are now the standard choice, offering instant brightness, dimmable options, and a wide variety of colour temperatures (from warm white to daylight). They are also far longer-lasting, with many rated for 15,000–25,000 hours of use compared to around 1,000 hours for a traditional bulb.

Types of Energy Saving Bulb

Today, the main types are:

  • LED bulbs: The most efficient, long-lasting, and versatile. Available in almost all fittings and shapes, including spotlights and decorative bulbs.
  • Smart LED bulbs: Increasingly popular, these allow you to control brightness, colour, and schedules via smartphone apps, voice assistants (e.g. Alexa, Google Home), or home automation systems. They often support dimming, colour-changing, and remote control, making them both energy efficient and highly convenient.
  • CFLs (legacy): Once popular, now largely replaced by LEDs. Slower to warm up and less efficient.
  • Energy saving halogens (legacy): About 30% more efficient than old-style bulbs but phased out since 2018 under EU/UK regulations.

To ensure you’re buying genuine energy-saving products, look for bulbs that meet UK energy label ratings (A–G). LEDs typically fall into the top categories.

Prices for LEDs have dropped significantly in recent years, and many retailers and councils still run promotions to encourage their use. With the efficiency gains and long lifespan, LEDs now pay for themselves very quickly through reduced electricity bills.

If you’re interested in reducing your energy bills even further, especially if you work from home, you may also want to explore whether a business energy contract with Purely Energy could be right for you.