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Carbon footprints and energy accounting

(last updated 05/03/06)

Inspired by my involvement with the Welsh Youth Forum for Sustainable Development, who have been looking at measuring household carbon dioxide generation as an indicator of energy use, I have been reviewing my own position at Penrhos and thinking more widely about energy accounting in general.

The current global consumerist view tends to see accounting only in terms of money. This has only limited use in considering whether systems may be sustainable or not as the real costs of products are often masked (by subsidies or price fixing for example) or externalised onto the environment (as pollution etc.) leading to inappropriate monetary values for goods and services. (examples)

A more realistic perspective can be provided by energy accounting. This requires considering not just the quantities and types of energy used by the system (oil, gas, electricity etc.) but also the energy embodied in materials and products that are brought into the system. So for example, we would need to look at not just the energy used to run a vehicle, but also the energy required to make it in the first place, maintain it and dispose of it at the end of its working life. Similarly for something like a windmill where we may find that the energy taken to make the device is greater than that which it can supply during its lifetime (though its worth considering this). Working out the embodied energy of materials and products can be time consuming and may require tracing components or raw materials all the way back to mineral extraction or whatever but it does give a much clearer picture of energy expenditure and hence aid in our decision making.

Carbon footprints

A simpler method of accounting is provided by the so-called carbon footprint. This is the amount of carbon dioxide your household produces each year based on your use of various forms of energy. By checking through your household bills you can work out how much gas, oil, electricity etc. your household uses each year. You'll also need the mileage of any car, bus, train or airflights. There are various calculators on the net (such as and if you enter the relevant details you can get a figure for how much carbon dioxide your household produces each year, usually in metric tonnes and compare your footprint with national and international averages.

Its well worth trying your figures in different calculators (do a search for "carbon footprint calculator" and you'll find stacks) as some offer more detail than others (such as make and model of car) and they use different methods to work out the results. In my own situation, lacking any mains services, I struggle to fit my details into the standard calculators. On the Penrhos household came out at 2.5 tonnes CO2 per annum which makes my individual footprint 1.25 (the household divided by the number of occupants, two in my case).

I've also used the Centre for Alternative Technology's Carbon Gym CD-ROM which as well as providing excellent information and suggestions for reducing your carbon footprint also has a more useful calculator that includes food and other everyday household activities. The CAT Carbon Gym is particularly good as when you have completed the footprint, you can change your previous answers and see the changes reflected visually. This immediate feedback is very useful for seeing the effects that result from taking different actions.

On the CAT calculator Penrhos came out slightly higher at 2.6, largely due to me being faced with having to choose gas for water heating rather than my current combination of bottled gas and wood heat.

Still not satisfied, mainly because I was having to fudge inappropriate questions for my lifestyle, like trying to work out a petrol generator's CO2 production by treating it as a small car, I decided to have a go myself. This means you can work out the quantities of the different energies you use and multiply by a coefficient to arrive at the CO2 figures. The information is generally available on the net although I am still stuck on some things. I have tended to overestimate and round up figures. As you will see, the resulting figure for the Penrhos household CO2 is still incomplete and any help will be gratefully received. I present this information as work in progress and would remind viewers that there will inevitably be mistakes in my calculations. I intend to add more detail and references for how I arrived at all the figures.

Tir Penrhos
energy use     
Kg CO2
500 30 16.67   123.10
4000 50 80.00   590.88
600       60 
no flying 
    50.00   369.30
embodied energy? 
as above? 
water wheel
space heating
wood heat
local source 
    4.00   29.54
some wood heat
LPG  180Kg   500.40
1 bag to landfill
per week
torch types  deep cycle       
1 box of six
lamp oil
not a lot      4 pints   
horse hay (one horse)  200 bales  per year  1000   miles  70 


Please note, I am not putting these figures up because I am proud of them because I am not. I must admit that I was ashamed of myself when I looked at all this due to my ongoing car usage and petrol generator (examples of my continued oil addiction). However, personal shame and guilt are useless hinderances that operate as stoppers in my work and it is up to me to deal with them (through support work based on the principles of good attention found in re-evaluation counceling). As I am approaching fifty and have taken huge amounts of flak over the years for my beliefs ("yoghurt weaving hippy" was one of the more printable descriptions of me by the authorities), its high time I stopped worrying about any illusory reputation and faced the facts. Then I can learn the lessons and get on with implementing the changes.

Some explanation of 2005 is in order.

I'll put more detail in here but very roughly, Lyn was diagnosed with cancer (again) in the early spring and a lot of our work on the holding was temporarily shelved as we dealt with her treatment (surgery and chemotherapy). Maintenance of various systems was much reduced and some failed completely during the year (notably some crucial fencing). This meant that 2005 represents probably our highest energy use since we first took up residence in 1992. Its useful therefore as a new baseline from which we hope to improve our energy efficiency considerably (ultimately we will all have no choice but to do this anyway). Anyway, our household comes out pretty low compared to national averages, so at least that feels positive.

So what?

What will happen to the energy I save? Will that oil stay in the ground? If I am honest then the answer is no. People will continue to extract and burn oil until it becomes too energy expensive to extract (that is, when it costs more oil to get it out of the ground than the amount of oil you get out).

So why bother to save at all? Here are a couple of (very good) reasons.

We are moving from a period of high availability of energy (to those of us who are rich- ie. Income more than a few pounds a day, say) to one of low availability (high prices, shortages, rationing). Energy descent is coming and the better we get at living low energy lifestyles now, the easier it will be to make the transition. (do a search for peak oil on the web, If you want to scare yourself).

We need to model low energy, low impact, community living as a positive step that results in relationships, activities and lifestyles that are more satisfying, fulfilling and fun than what we have now. For some of us we already know this but many people do not, both in rich and poor countries. Without viable, living models as demonstrations, most people are simply not aware that the so called alternatives are in fact practical solutions that can be implemented now and are better for us!

It is not possible for us to move from our present unsustainable system to one which is sustainable in one step; it is too big a leap. The process of creating sustainable systems requires the assembly of techniques, elements, ideas. Fitting these many and varied components into a sensible arrangement is a design process so we need design tools to aid us. That is why I practice permaculture design, which is the conscious design of sustainable systems.



Systems thinking

I think it is useful to think in terms of systems. We can see a household as a system; it has inputs (energy, information, food etc.) and outputs or products (waste, workers etc.). Thinking in terms of systems allows us to see ways of connecting up outputs and inputs efficiently. It is also the first step towards process thinking where rather than concentrating on the objects or elements that make up a system, we look at the flows of energy and processes that sustain those objects or elements. Carbon footprinting, for example, gives us some clues as to the process whereby carbon is moved through the planetary system and how our actions effect that process.




My transport to the launderette is already counted but obviously my use of their machines to wash my clothes generates carbon dioxide. I could just ignore this and say that this CO2 emission belongs to the launderette's or its owner's CO2 footprint, not mine, but this is the same as a business externalising some of its costs onto the environment as pollution so I really want to claim some responsibility here.

Usage is one large machine per week plus half an hour in a drier. Any suggestions as to CO2 emissions?



No Flying

Neither Lyn nor I have ever flown as adults. I flew twice when a youth, in 1968 and 1970 aged 12 and 14 respectively. It is amazing how much has changed since then. My Dad had already flown twice connected with his work. He was the second person to fly on our estate in Denby Dale, (then in the West Riding of Yorkshire) and we were the first family to fly. It was a hugely exciting time, preparing for what we referred to as "the trip of a lifetime". We did not expect to get the chance again as it was so expensive. Al our friends would call in to see how we were doing and when we got back we had regular sessions showing the four cine-films that recorded the 8 week trip (4 minutes each film) and various things we brought back (including butter packs from the in-flight meals that were considered very posh and modern).

Although as it happened we did fly again in 1970, that first trip, to Canada, Manitoba and British Columbia did turn out to be the trip of a lifetime, for me anyway. The Rocky Mountains opened my 12 year old eyes to the vast, awe-inspiring beauty of the world and particularly wild, natural ecosystems. I never felt the urge to go anywhere again and the second flight, to the US in 1970 when I was 14, was disappointing in comparison. That was the end of my flying career.

I now consider Chuang Tzu's simple phrase, "it is not necessary to leave your room in order to see the world".



Wood heat

Back in 1981, our current landlord upgraded the house we were renting from an open fire to a multifuel stove and I set about burning wood for space heating. I really enjoyed scrounging the wood from road side prunings, fallen trees and the like, the physicality of the work, sawing, splitting, stacking and that it cut some of my chains binding me to non renewable energy. In a fit of youthful exuberance after splitting and stacking some four tons of firewood I made a commitment to burn only wood from then on, for as long as I could continue the work.

Twenty five years later and I have kept to that commitment with one minor exception. In about 1989 my trusty Reliant Robin wood-hauler broke down (again) and was off the road for a fortnight. This coincided with running out of wood and one freezing afternoon in desperation I bought a bag of coal in Dolgellau, strapped it to the carrier of the motorbike I was using at the time (a Yamaha DR600 of my brothers, I believe) and set off for home. The bungee must have slipped off or something because about half a mile from the house the bag fell off (luckily no one else was around) and burst on the side of the road. I rode home and walked back with a brush and shovel and mused upon the ominous event, reaffirming my commitment to burn only wood.

Being well versed in the nature of scrounging helps as a wood collector. Roadside prunings are a good bet as often this will save the pruners time chipping or dumping. Farmers generally do not have (or make) enough time to clear fallen trees and my locality (17,000 acre forest) is liberally scattered with forest waste (calculated by the Forest Authority as 10% of output. When Coed Y Brenin was being stripped of its trees at the rate of about 100,000 tons a year, this meant a lot of waste).

Since getting the land in 1986 I have planted and managed trees on site for wood fuel. After twenty years large parts of the site are well stuffed with trees and I could be self sufficient quite easily. Much of this is self seeded birch and willow but I also planted these pioneers along with fruit and more valuable timber trees back in the late eighties. The pioneers have done their work well, drawing up the hardwoods and sheltering tender fruit and now I am gradually taking them out. Similarly, we encourage our native crack willow and coppice this when green as first animal fodder (leaves and bark) then firewood. More fuel wood comes from shelter belts and particularly our northern shelter which require regular management in order to maintain growth low down (ie. coppice). However, I still acquire stuff from off-site when a good opportunity arises (fallen oak near a road for example) and when I'm really tired and flush I buy some logs off friend Terry; this is a real luxury as he delivers them to the front of my fuel store and all I have to do is split and stack.

I'm reminded of what David Holmgren said when he taught here; Firewood is one of the lowest uses of timber and we shouldn't just plant for this reason. Rather we should plant for high value timber, for houses, furniture, food for ourselves and our animals and any firewood should be a byproduct of managing trees for these purposes.

Type of burner is important. The first I used, a Rayburn multi fuel, was horrendously hungry and at times I felt like its slave. Discovering proper woodburners (ie. Scandinavian) was a milestone and halved the amount of wood but lost the gallons of hot water. From my work on the holding its clear that for the (more) permanent dwelling (if, when...) I need to move to some sort of burner that will take branches and prunings rather than logs as my other actions generate a lot of this anyway. A rocket stove may be appropriate or possible a fast burn, high mass job along the lines of the Kakel oven.




In the early seventies, the motorcycle was considered to be the poor person's means of transport and I really got into the whole thing, generally running what were then cheap British motorcycles, like a BSA A10 and a Velocette Venom (wish I'd kept them!). There was a great sense of camaraderie amongst bikers in those days and one of the other bonuses was that wearing a leather jacket meant the skinheads shopped bothering me. I didn't get a car driving licence until 1991, mainly because, bizarre as it sounds, I found out that you could drive a three wheeler on a bike licence. This was odd as the first Reliant I bought I couldn't drive (I didn't know which pedal was which) even though I was legally entitled to. I spent a couple of days going up and down the track before venturing out...

With the addition of a tow bar and small trailer I moved considerable quantities of stuff with the Reliant such as about a third of a ton of firewood at a time. When we moved up to Dolgellau from Aberystwyth I did the removals with the Reliant, including one notable trip carrying Lyn, Sam as a toddler, a dog, a goat and a bale of hay. People would begin to overtake then slow down, staring in amazement at the occupants of the yellow plastic pig. I managed to keep the Reliant going for ten years. Often when it broke down I would breathe a sigh of relief, telling myself, now its finally dead. Then, after a few days I would crawl under it and potter and eventually get it going again. My last Reliant came to me through the death of a great friend, Eurig Ap Gwilym. This was a subtle brown and ran well for six months before spontaneously combusting, ironic as Eurig had been convicted of and served time for arson...

Since then cars have been more of a pain, more expensive to get, run and repair but they kept coming my way. The four by four appeared again because a very good friend died and I would rather have him back any day than that lump. We used this vehicle for a few years as it coincided with our involvement with the Rhiwgoch sawmill cooperative where it saw service delivering products and moving chip wood as a byproduct of the mill. It also tied in with the horse training as we could tow a box- some clients desperately wanted their horses to come to us for training for loading but as they couldn't load their horses, they couldn't get them to us. Plus it was easy to get Myra's (my mum in laws) wheelchair in it. With the folding of the mill and Lyn's illness it did less and less work until now its time with us is over.

The current vehicle came my way when my Dad decided he no longer needed a car and passed on his twelve year old Micra. This will do for now but I am mustering the strength of mind to have done with it and them once and for all. Watch this space.




I have had a love-hate relationship with horses for twenty years. To be precise, love the animals, hate the environmental destruction and consumption of resources that the owners of many horses demonstrate (usually unconsciously). After being married to a horsewoman for twenty six years I finally caved in two years ago and decided the only way I was going to be able to deal with this contradiction (the love - hate) was to undertake a trial to see if it was possible to keep a horse in a sustainable way and get some useful physical return from it, like transport and some work. I took on a Welsh Cob and am still involved in the trial.

At present she gets no hard feed, though when she comes into full work this may change. I have included her here as totally dependent on hay, which is not the case but makes a good baseline to start accounting from. She has about half a bale of hay per day so 200 is slightly overestimating her feed.

Back in the early eighties it was relatively easy to get hay locally as several farmers still made small bales as well as silage and were often pleased to shift any of last years hay that was left over. On our two mile trip form Llanelltyd to Dolgellau we would pass just two horses. In the nineties this had gone up to twenty horses and there was no local hay, everyone having gone over to silage. We switched to a local feed merchant (Blawd Ac Ati) who deliver hay to the barn. The origins of the hay vary from the Lleyn to the Midlands to the south.

I have arrived at a rough figure for the energy costs associated with the transport of a single bale of hay from source (taking it as southern England or the Midlands) to Penrhos. This assumes one lorry load (in the region of 400 bales) from source to the feed merchant first, estimated at a 400 mile round trip. Then five loads of 40 bales each from the feed merchant to Penrhos, estimated at a 60 mile round trip. This gives 700 miles as the total travel for my horse's 200 bales per year and I've worked it out at 20mpg which may well be too much.



Petrol generators

I had felt pretty guilty about using a petrol generator. Its a very inefficient way of producing electricity but because ours gets only occasional use, overall it produces far less carbon dioxide annually than the average household's use of mains electricity. Due to the temporary nature of our planning situation I had held back from investing in water power (dam repairs, pipework, turbine etc.) until inspired by my mate Jim a couple of years ago. Since then we've designed and installed a prototype wooden wheel plus gearing and electrics and now when the waterwheel is working, the generator isn't. I need to push on with this so its always working and the generator can be for emergencies only.



Inappropriate monetary values.

There are loads of these but here are a couple of mine.

Example 1

I can buy a sack of mixed grain (25 Kg) for my ducks and it costs me less than £5. I look at this vast sack of seed and imagine the rather meagre quantity of eggs I'll get from it (compared to many people in the world my ducks eat well). Surely something is not right here? Well for starters the price I pay does not include the cost of clearing up the pollution resulting from the use of the chemical fertilisers, pesticides and herbicides needed to grow the grain, nor the soil compaction, erosion and carbon dioxide released into the atmosphere resulting from ploughing, among many other things.

Something is indeed not right here. My primary reason for having ducks is slug control, not eggs and their natural activities on the holding allow me to grow more vegetables than without them; I say this from long experience (20 years) of keeping my feathered friends and would recommend Khaki Cambells above all other breeds as slug devourers par excellence. As a permaculture designer my ongoing challenge is to reduce the need for that external input of grain by growing more food for them on the holding. I blocked up drainage ditches on the previously drained marshes, constructed causeway dams and encouraged a lot more water storage. In frog season the ducks get fat and lay lots of eggs. We are getting there.

Example 2

Another odd money comparison for energy comes from candles. To light our home for an evening if we are just talking or listening to the radio takes 3 candles. If we have friends around or want to read we need a few more, maybe 5 or 6. So if we were going to use candles every evening for a week we might need about 20-25 candles. I can buy a box of 6 paraffin wax candles for £1.20 so lets say I might use four boxes in a week at a total cost of £4.80.

But this is (currently) more than the price of a gallon of petrol. I can't believe that four boxes of candles contain the same energy value as a gallon of petrol. Anyone got any clues as to what is going on?




The CAT carbon gym does usefully broaden the usual footprint out into areas of life other than the obvious ones of mains energy use and cars. So food gets a look in and you get to choose between home prepared meals and prepackaged meals or a bit of both. Despite being rather simple it does at least start to get to grips with the energy embodied in food through production, transportation, packaging etc. I'll be doing more careful work this year (2006) to record where my food comes from.

Obviously the best food you can eat to reduce your carbon footprint is what you can grow in your own garden, window box, conservatory whatever, (obviously from seed you saved last year and using compost from your kitchen warmer). Funnily enough that's probably the best food for your health as well...

Similarly, the solution to climate change is the same as that for developing sustainable systems, that is, the study and practice of permaculture design.



Energy devices versus embodied energy

My little Rutland windmill has been buzzing merrily for fifteen years (when its windy) yet I am doubtful that the energy it has produced over those years would be sufficient to make another windmill like it. However, there are still a number of arguments in its favour.

One such argument arises from comparing it to the energy costs of running mains through the forest to our holding. The important point to make though, I think, is that we need to take into account what we use the energy for. So, for example, if we use the windmill in association with a battery, electric fence energiser and electric tape fencing, we can exclude grazing animals from potentially productive areas (food growing, coppice, orchards etc.) or areas that will naturally increase in productivity when grazers are removed (such as in revegetation or re-generation systems). In these cases the increased productivity may generate far more energy or resources than the windmill consumed in its manufacture.


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