Wednesday, 16 May 2012

Saving Energy

Good Evening Lovely Readers

Back to a money-saving blog! 

We have very high energy bills in our modest 1960s detached house and I have been desperate to rectify this since we moved here five years ago. We pay, on average, £100 per month each for electricity and gas. On top of this we have two sets of water rates - one for supply of water and one for removal of waste water. Since #2 moved out last Summer and #3 went off to uni last September, the water rates have halved. We have a water meter so this is down to usage and I am thrilled. That still left the huge energy bills.

When we moved in, every room was lit by either one or two of these:


Some were chrome and others a dull silver; some square and some like this, but all had 4 bulbs. I found these bulbs very expensive to buy - at least £1.99 each - and in spite of what I read, I found that they lasted very little time. Looking at all of our other electrical appliances, I had a hunch that these were the main culprits. So I did a little research.

I found this little grid on the web comparing the wattage of light bulbs:

Comparitive Light Output of Light Bulbs
Ordinary Light BulbLow Energy Bulb
40 Watt7 Watt
60 Watt11 Watt
100 Watt20 Watt
150 Watt21 Watt
A standard bulb lasts around 1000 hours and an energy saving bulb lasts approximately 8000 hours.
Taking the 'low' lifespan figure, the costs of running a 100W bulb for 8,000 hours can be compared.
Costs of Running a Light Bulb for 8,000 Hours Compared:
Low Energy Light Bulb:
Cost of bulb £0.10 (I bought a
huge batch at Tesco when they had an offer on).
Cost of electricity = (8,000 hours X 20 watts / 1,000 KWH) x 10p per KWH = £16.00
Total Cost = £16.10
Conventional (Incandescent) Light Bulb
Cost of bulb 8 X 25p = £2.00
Cost of electricity = (8,000 hours X 100 watts / 1,000 KWH) x 10p per KWH = £80.00
Total Cost = £82.00

Just changing one light bulb will save me £65.90 or around £16.00 a year.

In our lounge there were (until today) 2 halogen light fitments with a total of 8 x 50 watt bulbs. So these lights were costing us approximately (because I am not sure exactly how long the bulbs lasted) 8,000 hours X 400 watts/1000 KWH) x 10p per KWH = £320.00 WOW!!!!

£320 - £32.20 (= 2 energy saving bulbs) = £287.80 saving

Today we removed the two fitments in the lounge, one in the hall, one in the dining part of the kitchen, one on the landing and one in a bedroom. Two bedroom fitments were removed a few weeks ago.

for 32 of these

We have replaced 8 of these      

This means that we have changed 32 X 50 watt halogen bulbs (= 1,600 watts) to 8 X 11 watts (= 88 watts)

The 8 fitments that we have already changed should give a saving of £1151.20. This is a truly staggering sum! We have 4 halogen fitments left to change. I am really looking forward to seeing the change in out bills.

I spent £1.49 per ceiling fitment (6), £11.99 each for 3 jewel shades and £1.49 each for 3 cream lamp shades (all QD). I think they look quite pretty.


How many bulbs have you got that you could change?

PS. I would love any energy experts to comment as I haven't done this before and I am only assuming that I have done the sums correctly. I think we pay more than 10p per KWH too.
How are you saving on your energy bills? If you have tips, do share them.

love Mrs Thrifty


  1. All our bulbs were changed a few years ago...the downside is that the energy saving bulbs cannot be placed in regular garbage here . The bulbs contain mercury so need to go to a safe disposal site.
    Jane x

  2. How interesting, we have changed the bathroom and hallway, so still have a few that need changing. Your energy bills do seem quite high compared to ours (we're in 1930's a 3 bed end terrace). It'll be interesting to see how this makes a difference for you. x

  3. I'm not sure the exact math on energy savings but they sure do last longer. We replaced some bulbs with energy-efficient 3 year ago when we moved in and they still work!!

  4. We won't use the low energy bulbs due to the mercury, it is BIG time dangerous if they become broken!!!. For our light fixtures with numerous bulbs I use 25 watt bulbs. We only turn on the lights when needed. We keep the thermostat on 78 during the summer, 63 during the winter. I also line dry most of our laundry and rarely use the dishwasher.

  5. Hello Mrs Thrifty:
    We did not do these detailed calculations but, after replacing our bulbs for low energy ones some months ago, we have indeed noticed a big difference in our electricity usage. We are sure that you will notice a big difference and that is all to the good with energy prices increasing, seemingly, by the hour these days!!

  6. was well worth sitting down and doing the maths there.

    You stand to save a fortune.

    Sue xx

  7. We changed ours to low energy bulbs a few years ago. We have similar light fittings in our kitchen & dining room, but like Debby said - the mercury in the bulbs is very dangerous!

    So we're now replacing all ours gradually with LEDs which are a safer option & use even less power. Our kitchen originally had 8 x 50W bulbs & like you, we found the bulbs needed replacing about every 6 months. We then put in just 2 x 11W low energy bulbs & now we have 8 x 1W LEDs - They give off a whiter light, but you get used to it!

    We found our electricity bill came down drastically when we made the switch.

    We are big into switching off everything when not being used. The only things that get left on are our fridge, freezer & alarm clock. Everything else is usually turned off at the mains - even our cooker.

    We have been paying £50 a month for the last 2 years, but now there's only 3 or us - we expect it to come down & that's even with using the washer & dryer for our work linen & towels.

    Kay :)

  8. All lights in our house with the exception of the dining room lights (rarely used) are energy saving. Last pre-winter, our electricity supplier put our direct debit up from £35 to £55. Blow that for a lark we thought. Hardly used our central heating, instead lived in one room with the wood burner. Result, our direct debit has just been reduced from the said £55 to £32 for the rest of this year!We are also just about to change to a water metre to save more money. We live in a 70's 3 bedroomed house.


Thank you for commenting - I do enjoy reading them xx