Are dishwashers more efficient than my hand washing?

We often hear that dishwashers, counterintuitively, use less energy and water than washing the dishes by hand. No matter how many times I'm told this, I find it hard to believe, so when I finished a load of washing up today, I took a few measurements so I could compare my washing up with those that have been reported. Firstly, I bailed the water out of the bowl with a measuring jug to see how much there was, then added a bit to allow for water that had sloshed over the side. I hadn't rinsed under a running tap without catching that water in the bowl, so I didn't have to add any for that. The total amount of water was about 5.5 litres.

I know, because I've measured it before, that water that I find hot to the touch is 43°C. It's pretty chilly out at the moment, so let's say the incoming main is 5°C and round it up to 45° for washing-up temperature (all approximations here err on the side of increasing energy usage in my test). Since water is very reliable in how much energy it requires to heat up, I can calculate that this would take 256 Watt hours of energy to heat, or just over a quarter of a kWh.

I then needed to know how much washing up I'd achieved. One load for me is until either the draining rack is full or the water is too dirty to wash any more. This tends to occur at roughly the same time, though I do more rinsing under the tap towards the end of the load, as the water gets dirtier. I noted down what I'd washed:-

• 4 glasses
• 2 mugs
• 1 tin can and 1 jam jar
• 1 measuring jug (not the one I used for bailing)
• 5 plates
• 3 bowls and a basin
• pestle and mortar
• 2 saucepans
• 2 mixing bowls
• 2 plastic trays that fruit came in, for recycling
• 15 items of cutlery

One load of washing up

See those pans on the windowsill behind? I used the dirty water from this load to soak them so they'll be easier to wash when I get round to them. I do that.

Having noted down the details of my own washing up, I then needed to find appropriate figures for comparison with dishwashers. The fact that dishwashers are more efficient seems to come mainly from a study conducted at Bonn University, comparing many people actually washing up with dishwashers doing the same work. When I looked for this study I was pleased to find that they've done a follow-up with smaller loads (the original study was a full twelve place settings in one go): Our intention was to simulate the dishwashing situation in a two-person household, excellent! ... in which two place settings are used and cleaned three times per day ah, I'm not sure I wash up that frequently, ... and four additional items are soiled heavily in the food preparation processes and are washed separately. Do you wash up the pans separately? Still, we should be getting close to comparable figures.

I looked at the details of the study. One place setting consists of:-

• a soup plate
• a dinner plate
• a dessert dish
• a cup
• a saucer
• a serving dish
• a glass
• a fork, a knife, a soup spoon, a teaspoon, a dessert spoon

So that would be a three course meal with coffee to follow, three times a day?? OK, never mind how unrealistic this is. I now have some details to work with. How does my load of washing up map onto this test load?

two place settings plus pans	my washing up
2 soup plates; 2 dessert dishes	3 bowls and a basin
2 dinner plates; 2 saucers; 2 serving dishes	5 plates
2 cups	2 mugs
2 glasses	4 glasses
10 items of cutlery	15 items of cutlery
4 pans/casserole dishes	2 pans; 2 mixing bowls
not included	pestle and mortar
not included	measuring jug
not included	tin can; jam jar; plastic trays

It looks like my load of washing up was slightly more than one of their two-place-setting loads plus their food preparation load. Let's say they're roughly the same - how do the figures compare with their hand washers?

The water and energy measurements show a very wide distribution of consumption values, ranging from four to 90 l and from 0.03 kWh up to 2.6 kWh for washing a pair of place settings. Washing four heavily soiled cooking items required slightly more energy and water than two place settings.

I used 5.5 l and 0.26 kWh for a pair of place settings plus four cooking items. For water consumption I am off their scale, and I'm way down there for energy consumption too (apparently someone was happy to wash up in cold water).

How about the machines? We need to take account of the fact that you'd put more in a machine than my one load done by hand. I estimate that you'd get two to three times as much in a dishwasher, and their test used six place settings (three times as many as one of their hand-wash loads) plus the pots and pans. I think multiplying my usage by 2.5 gives a fair basis for comparison, so that's about 14 litres and 0.64 kWh. Their machines used 83 litres. With regard to energy consumption (Fig. 8), the tendencies are similar, but the difference between manual and automatic dishwashing is not as pronounced. They don't even report the figures, but examination of their Figure 8 shows almost identical energy consumption for the 6 place setting plus pots and pans; approx. 1.8 kWh.

As I'd suspected, the current emphasis on low water consumption serves to distract from high power usage. When compared with my own washing up, as best I can, I am far more efficient than a machine in both water and energy consumption.

I finish by noting a sentence from their acknowledgements section: Thanks are due to our four European manufacturers of dishwashing machines (Bosch und Siemens Hausgeräte, Electrolux, Merloni Elettrodomestici and Arcelik) for supporting this study.

A beautiful thing

As I was walking down the steps to fetch in some firewood, I noticed this:

One small rose bay willow herb, seed pods dry and curled, having shed their seeds (liberally, all over my garden), casts the most exquisite shadow in the low autumn sunlight.

Unrepeatable Christmas cake

Or, What to do with a dead Herman.

As recipes go, this one's pretty useless, as a key ingredient is a friendship cake starter that's been neglected to the point of alcoholism. Other key ingredients are the remains of two tins of treacle that have been sitting in the back of the cupboard for approximately a decade, which I discovered when I went to put away the two new tins of treacle that had been on special offer in the supermarket.

Where was I? Oh yes, alcoholic Herman. If you neglect the starter for long enough, it will separate into three layers: Gloop on the bottom, froth on the top, and an alcoholic liquid in the middle. The first time I discovered this I tried drinking the liquid, but it wasn't as good as you'd I'd expect alcoholic cake mix to taste. Reasoning that wine yeast survives quite a lot of alcohol, I fed him and sure enough, he revived, but then I neglected him again. I've really lost interest in sourdough cake making by now. I've yet to find a recipe that Ian likes and it's distracting me from making cakes to tried and tested recipes, so all our cakes are slightly (or very) disappointing experiments.

The combination of alcohol, cake mix, and treacle (and the time of year) put me in mind of Christmas cake. I consulted my mum's recipe, which requires a 9 inch cake tin. Is that square or round? In any case, I don't have a tin that big. That one must have gone to my sister. I then consulted Delia, whose recipe for rich fruit cake was very similar (and even richer) and called for a 7 inch square tin, which is what I had. Using these two recipes as a very rough guide, my version consisted of the following:

1. Cut up the remains of a tub of glace cherries, a few dried apricots and two pieces of crystalised ginger, then make up to two pounds with a bag of mixed dried fruit (including citrus peel).
2. Add a tablespoon of brandy and the alcoholic liquid from the cake starter to the fruit, mix and leave overnight.
3. Feed the remaining Herman mix with about 4 fl oz each of flour, sugar and milk. Cover and leave overnight (it bubbled in a desultory manner. I don't think he was going to revive this time.)
4. Next day, soften/melt about half a pack of unsalted butter together with the remains of the salted in the butter dish - probably about 5 or 6 oz altogether. At the same time, put the treacle over the heat so it'll be easier to get the last bit out of the tin. When fairly liquid (because it's easier to mix that way), stir these into the Herman gloop. I didn't actually use all the treacle, but it was probably about three tablespoonfuls, or three times what the recipe said.
5. Beat a couple of eggs (half what the recipe said) and mix in
6. Add sugar (white) until it tastes sweet enough - about 4 oz
7. Add flour until the consistency looks about right - 8 oz
8. Add a quarter teaspoon of bicarb (how can such a small amount make any difference in so much cake mix?) and spices to taste - maybe half a teaspoon each of nutmeg and cinnamon, plus a little mixed spice.
9. Wonder about the grated lemon and orange rinds in Delia's recipe and remember the orange peels still in the freezer from making juice last Christmas. Get out a couple of halves and grate into the mix. They grate well when frozen.
10. Mix gloop into fruit (the fruit was in the bigger bowl). Look at resulting cake mix and think, That's never going to go into that tin.
11. Search cupboard for another tin. Find various fancy shaped things lurking at the back (did my sister get all the useful tins?) and settle on the loaf tin (oh no, I got that one.)
12. Line tins with a double layer of greaseproof paper, leaving plenty sticking up around the top of the tins, and grease well. I hate this job. There's no baking powder in this recipe, so it's OK that I put this off until I had the cake mix, um, mixed.
13. Fill tins with cake mix to a similar depth, then fold greaseproof paper to make a cover over the top of the tin, but don't seal or the steam won't be able to escape.
14. Bake at gas mark 1 (yes, really that low) for four and a half to five hours. I took the smaller cake out after four and a half hours, the larger after five. Leave to cool a bit
15. While they're still a bit warm (I'm not sure whether this matters, but it's the way Mum used to do it), turn the cake over, poke holes in it with a skewer, and pour brandy over it. I used the bottle cap to measure (and to make sure I didn't tip out half the bottle) so it wasn't that much. I may add more over the next month or so.
16. Wrap in greaseproof paper and try to find a tin that the cake will fit into for storage.

Since this was a very experimental recipe, with a much higher liquid content than the ones I was basing it on, and my track record with the friendship cake not being very good, there was no reason to expect this to turn out well, so I'm glad to have a spare one for testing.

It's important to test it thoroughly.

It's rather good, actually. Against all the odds, this is one successful Christmas cake. Now I hope it keeps!

A nice cardie

I live in Ceredigion, also known as Cardiganshire, so most of the locals could accurately be described as nice Cardies, but they are not the subject of this post. What I'm talking about is a woolly jacket.

When I went to a spinning class last year, I browsed other stalls at the festival and spotted some pure Shetland wool priced at £1.50 per 50g ball. What a bargain! I asked the advice of the more experienced knitters around me as to how much I'd need for a jumper (that's sweater to those of you living across the pond. I tried looking up transatlantic translations for cardigan, too, but it got very confusing. You'll see what I mean by the end of the post). No-one was keen to commit on quantity of wool required, but the best guess was twelve balls, so that's what I bought.

Then followed a long period of doing nothing much, but pondering design. I definitely wanted a cardigan rather than an over-the-head jumper, I want it as long as possible with the wool available, and I want it nice. I have smart office clothes left over from my old life, but those are rarely suitable these days, and I have scruffy clothes for working around the house and garden, but I don't have much in between. This isn't too much to ask from my first big knooking project, is it?

I started by making up a sample piece, trying out different knit stitches and practising buttonholes. I fancied a chunky knit but the wool was fairly thin, so I wasn't getting what I wanted. After a while it occurred to me that crochet would give a thicker fabric, so I tried a few crochet stitches and settled for counterpane stitch, taking just one loop from the previous row (as opposed to both sides of the loop. The difference is that the half-loops left behind make a line along the fabric.) Experiments with decorative stitches revealed them to be not very visible, so I abandoned those. I used up the whole ball of wool in my sample to give me an idea of how much fabric a ball would make. Ah. Not very much.

Knit stitches to the left, crochet to the right. The extra bit bottom right is crochet buttonholes.

As I was working with the wool it struck me that it's not very soft. I didn't think I'd want that against my neck, so I'd make the neck wide and add a collar in a softer yarn at the end. On the other hand, Pebble liked this little bit of woolliness very much.

Mine now.

A bit of investigation with holding this piece against my back and wrapping it round my arms indicated that twelve balls of wool would be enough, but only just. That was going to influence the design quite a lot. Firstly, this cardie would have to be quite tight, with fairly short, tight sleeves. I decided to knook the sleeves, as I'm quite happy to have them thinner than the rest, and stocking stitch will use less wool than counterpane stitch. I wondered if I could save some wool by adding some decoration in a different colour. I have some white that I bought for socks... stars! It has to be stars!

Once I'd had that thought, I then had to find out how to crochet stars. I found this tutorial which was good, but not quite what I was after. I took that as a basis and played around until I'd figured out a way of making individual stars. It's very fiddly and involves two stitch holders (twist ties). I'm sure there's a better way, but this works well enough for this project.

Test stars. Yes, Pebble sat on it again as I was taking the picture.

That was about as far as I could go with my test piece, it was now time to move on to the real thing. Since I wanted the cardigan to be as long as possible, that meant starting at the top. I also wanted to avoid sewing it together at the end, so each piece would be joined as I went along. I did have a look at patterns, but didn't see anything that particularly grabbed me and in any case, I can't read patterns. Making it up as I went along went like this:

Step 1. Make a foundation chain (I read about this somewhere, but can't remember where. You end up with the first row of stitches already in the chain and it's easier to carry on from there) for the neckline. This included a double row (there and back) along the top of each shoulder, where the seam would be if you were making it in pieces. I judged the length by draping it around my neck.

Step... um, I can't remember what order I did the next bits in. The front two pieces and the back were worked in turn, each starting from the top seam, with the front pieces increasing from the shoulders across the front. For simplicity, I decided on square-set sleeves.

Step 5. Continue those three pieces until they're long enough to join up under the arms. Rather than shaping round the sleeves, I decided to make the body pieces straight then add a gusset between waist and armpit. This meant the body pieces had to get all the way to the waist before they could be joined up. Since the stitch I'm using looks different on alternate rows, I had to be careful to make sure I was on an even row (or an odd row. It didn't matter so long as they were all the same) for all three pieces.

Step 6. Once I'd done a few rows of the joined-up section, I turned my attention to the gussets and sleeves. For these I switched from crochet to knooking, and chose a fairly loose stocking stitch for the gusset, then tighter stocking stitch for the sleeves. The first attempt at a sleeve went a bit wrong. I was reducing the number of stitches at a rate of one per round, which resulted in a pointed shape at the join, making a bulge in the armpit. I unravelled and started again, this time working back and forth round almost all of the sleeve, picking up an extra stitch from the gusset at the end of each row until there were none left and I could switch to working in the round. I'm not sure whether that makes sense or not - it's basically the same technique that I used for the heels when I made socks. The end result looked like this:

Armpit of the cardigan with sleeve at the top.
What looks like a seam is where I reduced the stitches.

Step 7. Shaping the sleeves involved much trying-on to determine how much I needed to reduce the rows as I went. Once I got past the elbow I did a couple of rows of stars, which was even more fiddly in knooking than in crochet. I then finished with a few rows of crochet for the cuff, for consistency with the body of the cardigan.

Step 8. After a few rows at the waist, I needed to start increasing the stitches. I measured, I calculated, I calculated some more, I largely ignored the results of the calculations, I forgot where I measured from, then the whole thing got messed up by the stars anyway. One way or another, stitches got increased by a couple per row, and stars were introduced shortly after that.

Step... ah, there's a bit I did earlier, but forgot to mention. I wanted an edging added for the buttons and buttonholes, but couldn't do this until the very end, when I'd have something to add it to. This somewhat disrupted my plan to keep going until I ran out of wool. I solved this by making up a section of buttonhole edging, unravelling it, and measuring out suitable multiples of that length of wool, which I then put aside.

Step 9. Once I'd got fed up of making stars, I put the white wool aside and carried on in blue until I ran out. This wasn't quite at the end of a row, but near enough that I felt safe pinching a bit of the reserved wool to finish it off. Front edging was then completed, leaving just this little bit of wool:

I felt quite smug to have used up my wool so precisely

Step 10. I raided Grandma's button collection for a suitable selection of buttons...

... and sewed them on.

At this point, I should have had just the collar left to do. Then I tried it on... it was way too tight. I'd known it was going to be tight, but thought the extra panels I added at the end would be enough for a comfortable fit. They weren't. I also discovered a flaw in the way I'd done the buttonholes, which was simply a row of triples. Effectively, I had a buttonhole between each two stitches and I just had to pick one that lined up with each button. That proved more difficult than I'd anticipated.

At this point it would have been very easy to get demoralised and give up. To avoid this, I quickly sought out my next door neighbour and showed her the (un)finished cardigan. She said all the right things about it being not that bad, and she was sure it wouldn't take much extra on the front edges to fix the problem, and how nice it would look when it was finished.

Thus encouraged, I went off to one of the wool shops in town to seek extra yarn. I wanted something soft for the collar, and thought it would be best to have the same yarn for the extra strips down the front, even though soft isn't ideal for buttonholes. I found some nice yarn (50/50 wool/acrylic) and asked the shopkeeper's advice on how much to get. I had in mind that two balls would probably be enough; she said four; I bought three. I actually used one and a half. I intend to take the last ball back for a refund, as a matter of principle.

Although the new yarn was thicker than what I had been using, I stuck with the same small crochet hook for the front panels, as I thought tighter stitching would probably be stronger for the buttons. I also changed the way I did the buttonholes so I wouldn't have the lining up problems that had emerged in the first attempt (which I'd unravelled and redone in plain stitch to match the other side).

For the collar I'd decided on double rib stitch and actually used knitting needles for this (larger, to suit the yarn). With knooking, rib stitch either comes out very loose, or is a right pain to do. Knooking turns out to be not such a great technique when you're switching between knit and purl stitches within the row. I found I didn't mind actual knitting as much as I'd expected. In fact, I might even go as far as to say I enjoyed it, though I did switch back to a crochet hook for the cast off.

Trying on the finished garment, I found that my neighbour was quite right - the fairly small strips I'd added made all the difference between not fitting and an excellent fit. Here I am modelling my creation in classic catalogue pose:

And here is a closer view:

I have to say, I'm absolutely delighted with how this has turned out. Not bad for a first big project, making it up as I go along, eh?