Showing posts with label usage. Show all posts
Showing posts with label usage. Show all posts

Friday, 3 April 2015

How much energy does YOUR house use?

A while back, I wrote a piece about the energy ratings on British houses, and I estimated our own house as being at the bottom of Band C, given our double-glazing, low-power lights, and recent condensing boiler.

So, with all that, how much energy do we actually use?

Our electricity usage is fairly constant, but our gas usage shows a seasonal cycle (there is a delay in the usage and the data, as we are billed every three month, so the "Winter Bill" appears in the data just as the weather is warming up.
In order to know whether any energy-saving upgrades are succesful, one has to know what the relative usage over time is.
Of course, as we have "gas" heating, the biggest factor in our usage is the temeratures that a particular winter brings.

That's me.
What about you?
Do you use more or less than us
(we have a "modern", in other words "small", 2-bed semi with a conservatory, and we live in the South of England)

Wednesday, 4 July 2012

Fuel consumption and speed - some solid data

It is easy to say that fuel usage increases with speed, and that wind drag is the major increasing factor.
But just how great is the effect?
Is it the same for all vehicles?
Does driving slower always save fuel?

Lets look at some hard data: page 29 in  Chapter 4 of Transportation Energy Data Book: Edition 30 - 2011, published by the The Center for Transportation Analysis at the Oak Ridge National Laboratory gives some figures for a variety of vehicles sold in the USA. Most of the vehicles reach their best economy at either 50 or 55 mph, with some of the physically larger cars better at lower speeds than that, and just one (the Toyota Celica - a reasonably aerodynamic sports coupe) being most efficient at 60 mph.

If that link is unavailable, then try here, which is a summary of the various data from the same source.
Just pick out the data list you think is the most relevant for you needs.
They all point to pretty much the same conclusions, whichever you pick.

Some important conclusions can be drawn, whatever type of automobile you drive, and whichever data source you choose: