Friday, 27 April 2012

Turned off by low energy bulbs?

Since moving into a new house a few years ago, we've been slowly replacing the ordinary light bulbs with energy-saving ones.

Everything has gone reasonably well, but there are a few lessons learned. As they seem to be the same things that turn other people off low energy lamps, I thought they were worth sharing.


A CFL Bulb
Image credit: Nroose
These are fluorescent light bulbs, and are what most people think of as "energy saving". However, I had two issues.

Firstly, they were not very bright, especially for the first few minutes. This was a problem on the stairs - but it was easily cured by buying a slightly higher powered bulb. It still uses less energy than the filament bulb it replaced.

Second were the energy costs to transport the bulbs all the way from China, where most of them seem to be made. I eventually found some made in Hungary, which is at least closer to home; though they probably go by road, so I can't really tell if they're greener.


LED bulbs use less energy than CFLs, they switch on instantly, and they don't need to "warm up" to give their full brightness.

LED bulbs
Image credit: Fcancela
Most of the cheap 1 watt LED bulbs are very dim, and I found they are best suited for background or decorative lighting. They tend to have a clean white light that is easier to see by, but it can look harsh compared to a normal bulb.

More modern LED bulbs are rated at 3 watts and above. There are some that are designed to mimic the warm colour of a normal bulb, rather than the brilliant white light normally associated with LEDs. And, in a contrast to normal energy saving bulbs, I found I could get away with a lower powered bulb than I expected, even though it was one of the "warm" ones.

LED bulbs cost a lot more than CFLs (£15 upwards), but they use even less energy and last a very long time. I calculated that they'll pay for themselves in a few years in our kitchen, where they have replaced halogen downlights.

A bright idea!
Image credit: Oscarjosue


I tried to replace the old bulbs only when they blew. Despite the fact that the newer bulbs use less energy, there's still a lot of energy used in their manufacture. Besides which, there's no point throwing away something in working order!

The Verdict

I'm convinced that energy-saving bulbs *can* work well. But as with many things, it helps to have a bit of insight, and not pay too much attention to marketing hype.

Image credits:
"Cuerpo humano jaqaru" by Oscarjosue, CC-BY-SA licence. Obtained via humano jaqaru.jpg.
"Compact fluorescent straight" by Nroose, public domain. Obtained via
LED lights based on an original image "Green Ray Lights" by Fcancela, Free Art Licence 1.3  Obtained via Ray Lights.jpg.

Thursday, 19 April 2012

Making money from the sun?

A close relative was visiting us at the weekend, enthusing about a new money-making scheme she'd signed up to: solar panels.

A salesman had called round, and sold her a grid-connected system - in other words, the solar electricity she doesn't use gets put back into the electricity supply network for others to use. And, because she's effectively running a miniature power station, she gets paid for doing so.

The salesman estimated that the system would pay for itself in 6 years. But this seemed overly optimistic, given the small size of the system he quoted. The government has publicly said that they will subsidise the payments to solar generators for many years to come. But there's something about politicians' promises, in combination with salesmans' promises, that made me feel uneasy.

Thankfully, another relative used to work for a renewable energy company, so we were able to support our opinions: solar PV may be a good way to help save the planet, but we don't view it as a get-rich-quick scheme.

Thankfully, there's a cooling-off period on the contract, so there's time to reconsider.

Is there really a money-making opportunity in solar PV panels? And where does the money come from?

(photo credit: Solar Panels by Ell Brown, licenced under Creative Commons CC-BY licence, obtained via )

Thursday, 12 April 2012

Beyond marketing: juice concentrate

When I look at fruit juice labels, I always find the phrases "not from concentrate" or "made with concentrated juice". I often wondered what this meant, and why concentrated juice is usually cheaper.

But is one really better than the other? I did some research, and found that the answer is far from clear cut.

Concentrates start as fresh fruit juice, but some of the water is evaporated. The resulting concentrated juice takes up less space, and uses less energy to transport. If you're shipping orange juice from (let's say) Brazil to Europe, that seems a pretty important consideration. Eventually, when the concentrate arrives at the juice factory, the missing water is added back in and the juice is delivered to the shops.

Juice marked "not from concentrate" doesn't go through this process. This makes it sound fresher, because it's squeezed closer to home. But it does mean that the whole fruit has travelled further, as opposed to just the juice from the fruit - which means more Food Miles.

In terms of nutrients, the government's "five a day" campaign makes no distinction between types of juice - one glass of juice equals one portion of fruit.

Which gives something of a dilemma. Unprocessed and fresh, or fewer food miles: which do you go for?

(Photo credit: Orange juice carton by Gerald_G (CC0/public domain licence). Obtained via: )