Friday, September 30, 2011

How to Save Power at Home, Part 1

Dear Reader,

A great many apologies for not posting last week; I'll try to be a bit more on-the-ball.
Now I'm sure you've noticed that I've been telling you quite a bit about new technologies that might hit our shores... a long time from now. Which is interesting and all, but not overly practical. So, I'd like to give you a bit more down-to-earth information, particularly on ways to save power.

Now, some of things I'm going to cover in the next few weeks you're probably already doing; but you probably don't have much of an indication of exactly how much you could save if you were doing them, and whether it was worth making the changes to get the savings (if changes needed to be made).

But, before I can get into all that, I need to show you what assumptions I'm making:

1. The power bill is $250 (if your bill is smaller, find out how much smaller by percentage, and apply that percentage to the amounts I work out).

2. You're being charged a flat-rate of 20 cents per kilowatt-hour (kWh); I'll write cent amounts in dollars from now one, i.e., 20 cents is $0.20.

3. The bill spans for 30 days.

4. Water flows out of the tap at 10 litres per minute (don't worry: this'll be relevant later).

5. Water flows out of the shower-head at 14.5 litres per minute (also relevant, but later).

6. Hot water heating accounts for 30% of the bill (based on what the EECA Energywise website says).

7. Space heating (heating done to heat rooms) accounts for 29% of the bill (see the Energywise website).

8. Lighting accounts for 8% of the bill (Energywise again).

OK, now that we have a groundwork done, let's have a look at lights.

I'm pretty sure you've guessed that I'm going to tell you to change to those cork-screw compact fluorescent lights - and I am.

But you might not know why, in the first place, the old incandescent light bulbs use so much power; well, around 98% of the power they use is actually converted into heat!
This is because they have to run electricity through a very thin bit of wire that has to heat up until it's white hot. And, it takes a lot of power to become white hot (go figure, eh?).

So, how much would you save?

75% on the lighting costs, and about 6% on the overall bill.

The reason for this is because the fluorescent light bulbs use about a quarter of the power used by the incandescent light bulbs.
Here are the sums:

15 x 60W incandescent light bulbs x 4 hours on a day x 0.2 x 30 = $21.60 every month
15 x 15W fluorescent light bulbs x 4 hours a day x 0.2 x 30 = $5.40 every month
And to work out the savings we go: 21.6 - 5.4 = $16.20
And to work out the difference it makes to the overall bill: (16.20 / 250) x 100 = 6%

OK, 6% isn't huge, but they'd pay for themselves in 4 months, since:
(15 x 8.99 (the cost of a 2 pack)) / 2 (since they come in a 2 pack) = $67.43
And to work out how long it'd take, we divide the cost by the savings: 67.43 / 16.20 = 4.14 months.

4 months for it to pay for itself? I'd say that's pretty good.

Next time, I'll have a look at why the fluorescents give off a funny light, and what you can do about that. And I'll have a look dangers they could pose with the mercury they use.

Yours sincerely,

Andrew Greaves

Wednesday, September 14, 2011

How to Charge Your Car for Free

Dear Reader,

Yes, charge your car for free by using the sun.

Of course, you'd have to own the i-MiEV (said 'eemeeyev' in a drunk Russian accent) - a little electric car. But, SolarCity is offering to install a solar generation set-up to power it - which results in the car not running up your power bill.

So, not a bad idea, except that the solar set-ups start at around $9,999; and, the amount of sunlight the solar panel would get is probably a lot less than what they reckon it could get (so you might have to get a few more than they say).

But I really do like the idea of an electric car not using your electricity.

Yours sincerely,

Andrew Greaves

Thursday, September 8, 2011

Watch Those Smart Meters!

Dear Reader,

Yes, beware! Allow you to monitor your power usage they would, but there are a few things to remember if you're looking at having one installed:

1. Not all smart meters are compatible with other power companies' technology.

Bit of a problem if you want to change power companies, eh?
Also, if you were to get a smart meter, then change power companies, the new power company might not have smart meter technology, so you'd have to go back to estimates.

2. You may have been undercharged (and they'll want back pay!)

To be fair, if you were undercharged, you should pay up - but it's hard to feel any sympathy for the power companies, isn't it? Just be aware that you could be lumped with an amount you hadn't bargained for.

3. Be wary of dangerous CRS (Contractor-Related Shoddiness).

Remember, this is stuff to do with electricity, so the last thing you want is someone doing a shoddy job! If you have a reliable electrician, and you're a bit wary of the job done by the contractor installing the meter, get your man to have a look at it.

For anyone that has changed over, or is thinking of it, know that you can lay complaints with the Electricity & Gas Complaints Commissioner.

So, now I'm sounding like a complete gainsayer; but I'm not against installing a smart meter, since you can monitor your power usage pretty accurately - which is superb if you want to know what you should turn off or use less of.

Just saying, weigh up the costs.

Yours sincerely,

Andrew Greaves

Monday, August 29, 2011

How Your Shoes Can Charge Your Phone

Dear Reader,

Yes, the scientists over in America are developing a shoe that's able to charge your phone! Imagine that: you get a call, knowing that your phone is probably going to cut out halfway - so you plug it into your shoes, and go for a walk around the office.

It might be a great nuisance to your co-workers, but I think it's a pretty clever idea.

So, how does it work? Well, that's quite interesting: there's a little technique called 'electrowetting', where you can get a liquid to wet a previously unwettable surface by charging it with an electrical charge. You can see it happening here.

It's been discovered by some clever man that the process can work in reverse, i.e., deform a liquid used in electrowetting, and it'll generate a bit of electricity.

The problem right now is that that bit of electricity is a bit too small to do anything with, but he reckons he can get it to be a big enough bit of electricity to charge a mobile phone (or even a laptop).

It may even have defensive capabilities, like running away from a mugger for 5 minutes, then giving him an electrified boot in the shins - no, that's close to impossible, but it'd be funny alright!

Yours sincerely,

Andrew Greaves

Wednesday, August 24, 2011

How Optical Illusions Can Help You Save Power

Dear Reader,

From the scientists over in America, a way has been suggested that would allow us lowly power users to save power through optical illusion.
The way? Create a length of tape with numbers on them that fits neatly over the meter, so that the meter reader's optics are illusioned...

Just joking - don't go reporting me, thanks. No, the real way is far more interesting. It goes something like this:

All your light bulbs are run on AC electricity, which means that they 'flicker' (sort of). The reason for this is because the current goes one way, stops, goes the other way, then repeats - meaning that the light, at some point, turns off. Sort of.
I don't want to get too technical, but the point is that it 'flickers' at such a high rate (60 times a second) that we don't even notice it.

Now, what they want to try and do is keep it on for 70 milliseconds, turn it off for 10, then turn it back on. Basically, this alters the 'flickering' so that it stays off for a bit longer than normal - about 12.5% longer - and you wouldn't even notice it.

And this 12.5% translates into 12.5% savings. Sort of.

Why all the sort ofs? Well, it's difficult to get reliable testing out of optical illusions because people's brains respond differently.

Anyway, onto the figures: the EnergyWise website reckons that 8% of the bill goes on lighting. So, in a bill of $200, you'd be spending $16 on lighting.
If you were to save 12.5% on that, you'd have saved yourself a great big $2 a month!

Well, it's a bit underwhelming, I suppose; but now you can go and give an interesting little tid-bit to your mates.

Yours sincerely,

Andrew Greaves

Monday, August 15, 2011

How to Illuminate Your House (Cheaply) Without Looking Dead

Dear Reader,

Just recently, I had a look at a light bulb that would save as much power as those compact fluorescent light bulbs, without the peculiar attribute of projecting light that made people look dead.
You see, at my age, you become quite concerned when you see yourself in the mirror; and even more so when you're lit up by fluorescent lighting!

Anyway, they work along the same lines as Cathode-ray tubes (have a look at my newsletters, where I go into a bit more depth about that), but without all the nasty x-rated-rays; apparently they also shine in all directions (as opposed to in beams), the light's a bit warmer, they don't contain mercury, and they reach peak brightness a lot faster than the compact fluorescent light bulbs.

They're also said to be better than LED light bulbs because they don't have a sharp peak in the blue section of the light spectrum - this is good because blue light might be damaging to the eyes. But, I'll go into that more a bit later on.

So there we have it: a new competitor that gives light that makes things look like they're illuminated by incandescent bulbs, with the lifespan of fluorescent bulbs. Be one to look out for, I reckon.

Yours sincerely,

Andrew Greaves

Thursday, August 11, 2011

3 News Pieces Tenuously Related to Power

Dear Reader,

As the title suggests, I found a few nuggets of interest; and yes, they are related to power (sort of):

First, BP has brought its petrol prices down a sliver to $2 (or thereabouts); marvelous, I said!
At least, I thought so until I remembered that a few years ago they were closer to $1; I suppose it's a little like being happy about tax rebates until you realise that the money was yours to begin with.
Anyway, how are the petrol prices related to power? In a few ways, actually: petrol prices might mean lower power bills, i.e., doesn't definitely mean lower power bills. This is because it has the potential to cost a tiny bit less to run the various machines (possibly through lessened oil and diesel costs).
Don't hold your breath though: I'd say that this is more like one of those things where the change only happens in one direction, i.e., when petrol prices go up, power becomes more expensive, but not the other way around.
Still, that's a bit of extra money in the pocket.

Secondly, Wellington homes seem to have benefited from a bit of extra insulation, thanks to, in part, EECA grants. Having had my own home retrofitted with insulation in the roof and under the floors, I can say it makes one huge difference: now there's actually a point using heaters, because the warmth doesn't escape the instant it comes into contact with the ceiling!

Since I'm a bit of a figures man, though, I'll give you a few percentages to consider:
Installing insulation in just the floor and ceiling keeps up to 50% of the heat in; so, assuming that 50% less heat-loss translates to 50% less heater usage, you'll be saving about 14.5% on the overall bill - if we go on the EECA's figures.

To get more details on how to make the most out of heating, though, sign up to get my free newsletter.

Thirdly, an author over at Scientific American has taken it upon himself to review 20 applications for the iPhone; and what do they do? Determine the amount of tilt your solar panels need to get the maximum amount of sun for power generation!
Well, I think it's quite impressive. It also means you can really interfere with the work of the guy trying to adjust the solar panels.

Yours sincerely,

Andrew Greaves