Sunday, January 22, 2006

28% Gas Saving From Simple Changes! That's £130 off my winter gas bill!

It's now a week since I made those changes to the programmable thermostat, and here are the results so far.
At 1:30pm today, almost exactly a week later, the gas reading was 7062.6 cu mtrs. Last week was 7041.0, so I've used 21.6 this week, compared to 30 the previous week.

If that translates to the whole year, then I've just knocked my annual heating impact down from 1.5 tonnes of CO2 to around 1.1 tonnes. Given two of us in the house, then it means that my gas alone accounts for 55% of my target of 1 tonne per year. That's a big improvement, it was 75%.

I'd still like to get it down to something a lot less, but it's a great start!

Sunday, January 15, 2006

That soak in the bath: 1kg or is it 0.5 ?

Just checked before and after for my weekly indulgence (in place of the shower), and it's 0.5 cu mtrs, which translates neatly into 1 kg of CO2.

Considering that the sustainable personal budget (to avoid catastrophic climate change) is said to be only 400kg/person/year, then it's a fair whack, but as it is I thought it might be higher. Shows how poorly insulated our homes are that it takes the heat energy of 60 hot baths to heat my home for 1 week.

Anyhow... off for a soak now... and then... I'm going to reclaim half of the energy by not emptying it until tomorrow morning... it can give it's heat off to the house, before being released, rather than to the outside world :O)

Thermostat & timing changes... let's see..

So, I checked out my thermostat settings.. which are admittedly a bit of a compromise as out of the two of us in the house, there's often one working from home during the day. Anyway, I'm sticking with a consistent setup all week, and we'll see how things go.

Previous was: (time -> temp)
  • 6:50 -> 18 deg C
  • 8:00 -> 16
  • 18:00 -> 18
  • 22:50 -> 11
I think it's too warm too early, and I could easily let things get cooler for the bulk of the day, so changed it to:
  • 7:30 -> 18 deg C (later, as I'm never up before 8... as it's not light yet by then will see if housemate notices!)
  • 8:45 -> 14 (allow 2 degrees cooler for bulk of day)
  • 19:00 -> 18 (I typically work later, and get home around 7pm. Can always boost temp up a little if in early)
  • 22:50 -> 11 (as before)
The other thing to do is to work out the footprint of my weekly indulgence... a long soak in the bath. We'll see about that one in a few hours.

A week in the life of my boiler

It's been pretty mild the last week... typically 10 degrees during the day, and still around 5 at night, so not yet the bitter winter people predicted.

Just under a week ago (9:50 in the evening), my gas meter read 7011.229 cu mtrs. Now, at 2pm the following Sunday, it's 7041.039. With a little rounding, we can probably call this 30 cu mtrs for the week.

Looking back on last weeks calculations, I can find out what I'm producing in CO2 emissions for a mild winter week. The figure I came up with last week (please someone, feel free to give more accurate figures) was one tonne of CO2 for every 500 cu mtrs of gas. So each cu mtr produces 2kg of CO2. So this week it was 60kg. If this was the case for the whole year, that'd be 3 tonnes of CO2 per year (rather than the 1.62 tonnes I calculated last week).

Mmm... time to find a way of cutting this down. How about reviewing my current thermostat settings... perhaps I'm putting the heating on far too early in the morning... I'll make some changes and see how things are next week.

Monday, January 09, 2006

Too Hot Here, Too Cold Then, Too Little Control!

I think we've probably all experienced that situation of having one room too hot, another too cold, and the house being heated when not needed, and not heated when we want it!

So, one area I can attack is to find out what I can save by improving my central heating control system. Let's start by having a look at what I've got, what it does, and what I'd like it to do.

I currently have digital thermostat controller with the following features:
  • it allows me to programme 6 different time periods at different target temperatures for each of 7 days of the week,
  • "holiday mode" - sets a constant reduced temp of my choosing for however many days I specify)
  • "sick mode" - press a button, and it'll use Sunday's settings for the rest of today - rather dumb considering that none of my days of the week is the profile I'd have if in all day!
  • "party mode" - extends the last time period by however many hours you want, so if you have a party, you can just add some 'warm hours' to the day.
In addition, each room radiator has a reasonably modern thermostat (radstat), that with a bit of effort I can get to behave.

Unfortunately, it's not designed as a system! It has the following notable drawbacks:
  • The main digital thermostat is in my hallway, so it relies on the hallway radstat being open a reasonable amount for other rooms to get warm.
  • The radstats are simple and have no variation... they're completely independent of the main controller.
  • The main controller, while being very clever, and the best I've ever had, is too clumsy to operate (and it's good by comparison). It's rather like old video recorders.
What I want is a heating control system that does the following:
  • It senses where people are and prioritises heating to those rooms, allowing other rooms to stay cooler, and therefore loose less heat through the walls.
  • In each room, it integrates with the alarm clock, warming the room ready for when a person gets up (and poss lighting the room or opening blinds). A simple wall mounted interface would allow the alarm clock to be silenced once out of bed, so it can learn when the target temperature is needed. Or, a motion or floor pressure sensor would detect when someone is out of bed.
    This alarm clock feature allows the heating to be set without even realising we're changing it. And... on a weekend, when no alarm is being set, a default could kick in at a lower target temperature.
  • Morning routine is complimented by having other rooms in the house, such as the kitchen warmed up in time for the earliest riser of the household.
  • Once people are up, a daytime mode starts, where the system detects who is where, and maintains a comfortable room temperature in the active rooms. Naturally, the bedrooms would probably be left to cool.
  • Control panels in all rooms would allow simple room by room overrides, allowing the occupant to indicate to that controller that they want the room at a given temperature for a given amount of time.
  • Lastly... budget. The heating control system would preferably be able to be given a budget (e.g. 20% less gas than last month), and adapt temperatures and timings accordingly. A system that fits within hard boundaries would be excellent for having people learn to do the obvious (go to bed earlier in winter, put on a sweater, indulge in some heat generating activity, etc.)
  • And... measurement. An intelligent control system should be able to measure heat delivered to each room (volume of water * temperature difference from one end of radiator to the other). This can then indicate which rooms are consuming the most heat, and would therefore most benefit from improved insulation. This in itself could be a system that can be temporarily installed once someone is using an intelligent system. Also, if the valves are all controlled centrally, then having only one open at a time would allow the proportion of flow to each room to be measured, and the temperature change could also be measured at the boiler. In effect, the control system heats only one room at a time, and either measures the temperature difference at the boiler, or the gas flow rate. All that would be needed is a flow meter and two temperature sensors. The rest is just maths.

Sunday, January 08, 2006

So what are the facts about my current heating?

So, what is the current CO2 balance sheet for the heating in my house?

According to what I can decifer from my latest gas bill, and my monthly £22 charge, I use 800 cu metres per year.

The calculator at the EPA Global Warming Resource Centre wants this in cubic feet per month, so lets see:
One cubic metre is 3.33 * 3.33 * 3.33 = 37 cubic feet, so my usage is 29600 per year... let's call it 30,000 cubic feet, which gives us 2500 per month.

At the EPA average price of $6.51, that equates to $16.28 per month (that's less than half what I pay.. which works out at $39 per month! No wonder you in the US use more, you pay half!)

Back to the subject... plug $16.28 into the EPA calculator and it tells me my house produces 3,557 pounds of CO2 (against their two person household average of 11,000).

Now to get to tonnes... a kilo is 2.2 pounds, so a tonne is 2200.

So the final figure is that my 800 cu metres of natural gas used to heat my house causes 1.62 tonnes of CO2 per year!

So, for those of us in the UK that's one tonne for every 500 cubic metres!

Mmm... as my gas meter reads in cubic metres, I'll take a look at the reading, and see how I'm doing in mid winter... okay.. at 9:50, its 7011.229 cu mtrs. Let's see what the score is in a few days.

The Challenge!

I'm starting this blog as part of a challenge I've set myself.

That challenge is to reduce my personal yearly CO2 emissions to 1 tonne (this is still about 3 times what is sustainable on average across the globe. The UK average is apparently 10 tonnes, and the US average 20 tonnes!).

The challenge once this is met is to live an extraordinary life, and to share with the world what it is possible to do within that limit.

My first challenge is getting there though, so I've started this blog to track one thread of the challenge... to reduce my fossil fuel heating emissions.

The overall challenge can be found on another blog - One Tonne Challenge which will track progress on all fronts.

This blog is intended to be a resource for people who want to tackle their heating emissions.