Sunday, May 22, 2011

The F word

No, not the rude one! I want to talk about flying. I am afraid to say that we flew over east on our recent holiday. We looked into driving (too slow and tricky with a 4 year old) and taking the train (about 10 times the price of flights and much slower), but it just didn't make sense. Of course the other option would be to not go, but we really missed our friends and decided to go anyway. I know I've probably disappointed some people (sorry bro and Ciaran). The last time we flew was to the UK about 3 years ago for my brother's wedding (yes Julian, it was your fault and when we get to the pearly gates and the carbon accountant gets out his calculator I'll tell him to put it on your account!) so we're not regular flyers by any means. I still felt bad about it none the less.

Maybe feeling bad is the best way to go. We emitted 7.8 tonnes  of CO2e according to an offsetting company, which is about a quarter of the average australian household's annual emissions. Let's say our family emits half of the australian average, this means that we have just emitted 6 months worth of our annual quota in about 8 hours! We should be ashamed of this and we are.

We could apparently offset that by paying for the planting of 47 trees at a cost of $167. No worries I hear you say, problem solved. But there's a catch. We made the emissions now and time is of the essence with climate change. Even if those 47 trees do sequester the right amount of carbon to offset our flights, it will take them 70-100 years to do it (I measure trees for a living so I should know). Do we really have 70 years to act? I don't think we do have time and I owe it to my son to minimise my emissions as much as I possibly can right now. Personally I think offsetting is at best a last resort and sometimes it can be a con (if you do offset I'd definitely choose a not for profit group). I could pay my $167 and clear my conscience but I'm not going to because I don't buy it. I just don't think it's the answer, so I'd rather live with the guilt and fly less (or not at all?). My family live half way across the world and I'd just like to say sorry I don't visit more often, but I hope you understand why.

Amy has a theory that people just shouldn't marry people more than a few hundred kilometres from their place of birth. That way we wouldn't have the ridiculous situation we have now where grandparents fly half way round the world every year to see their grandkids or kids having to fly accross Australia every school holidays to visit their 'other parent'. If we stayed all provincial, like in the olden days, no-one would have the heartache of leaving loved ones behind. Thankfully Amy formed this theory after she met me!

I have talked to people about my guilt about flying and most people just don't get it. They laugh and say that my footprint is so low not to worry about it, or some just don't understand what I'm talking about. We have such a culture of flying now that it's just normal to take 1 or 2 flights a year. A while ago I heard of someone who worked for the UN in climate change policy who commuted from London to New York every fortnight! And now we have the FIFO (fly in fly out) phenomenom in Australia, where tens of thousands of mine workers fly from cities to mines and back again every 7-14 days. The mining companies don't want to pay for building and supporting rural communities near their mine sites and of course they don't pay for the emissions these flights put out. This is a big blind spot for lots of folk.
EU flight emissions are up 110% in the last 20 years and India and China haven't even started flying in a big way. Let's just hope we get a price on carbon soon and flights start to become more expensive than trains. Please think about this the next time you plan a holiday. You could even make a pledge not to fly for 12 months at lowflyzone. It may be cheaper to go to Bali than a closer destination, but that's because future generations will pick up the tab. 

Flying, it's a four letter word in my book...

Wednesday, May 11, 2011

Solar year 3 ends

When we got photovoltaics (PV) on our roof 3 years ago I, like many people, didn't understand how it all worked. I really wanted to so I wrote a spreadsheet (Solar Tracker) to help work it out. Once a week I take readings from our inverter and power meter and enter them into the tracker. It has grown from a very simple thing to a vast sprawling monster spreadsheet which calculates way too many things, but I love it. I know how much power I use, generate, feed in, can predict bills, etc.....Anyway, our solar year runs from late to April so the exciting results are just in, so here we go. This chart shows weekly usage and generation (printed and scanned, still working out blog technology) and a summary below of stats.

The chart shows our usual pattern of higher usage in winter with low generation, then a cross over in spring to lower usage and higher generation. I'm pretty proud of the fact that we have continued to use less power than we generate with a very small system (1.1 kW Kaneka thin film amorphous grid connected, facing due North). Our usage is about a quarter of the average for West Australia. It was nice to get a credit of $167 for the year after 2 years struggling to pay our $20 bills! The reason for the credit is the introduction of a net feed in tariff to WA in August 2010. Under this incentive program the state government and utility company pay 47 cents per kWh fed to the grid, which is more than double the 22 cents we pay to buy in the power. Since we feed in 77% of what we generate we do quite well out of this program and next year our bill should be a credit of about $220. The feed in tariff is guaranteed for 10 years which has cut the payback time of PV from about 15 years to 5 to 8 years for most people. BAU means business as usual, so what our bill would have been without PV (so we saved $600 this year). Smart Power is a system whereby our power provider charges different tariffs at different times of the day. The advantage of this used to be greater for us but is lessened by the feed in tariff, but we still gained a bit.

The beauty of having 3 years of data is that we can compare this year with previous ones. Here is a chart of our cumulative usage in years 1 to 3.

This year we scraped in using slightly less power than last year (probably thanks to our holiday!). Our year before PV we used 6 kWh a day and we cut that by 25% in year 1. Then we cut our usage by about 8% in year 2 but it's getting harder now. I just found out that our answering machine uses 0.3 kWh a day, which might not sound like much but it's 7% of our consumption. If you try to call me and can't leave a message I'm afraid that's why (it's going to the op shop I think). So hopefully we'll be able to cut our usage to 4 but I think it will get harder and harder. One great thing about taking readings is that we can see the results of our behaviour change, it's a positive feedback loop which reinforces what we are doing. Before PV I didn't have a clue how much power we were using, even though it told me on each bill. By the way, if you're not sure how much you're using, your bill will probably say how many units you're using and a unit is 1 kWh. If you have PV, your utility company will estimate how much you're using based on the size of your system. If you want to know exactly you need to do some maths and take some readings. Take a reading form your inverter, which should tell you something like E total (numbers of Kwh generated since day 1). Then take a reading from your power meter, there should be 2 figures, 1 positive (taken from grid), 1 negative (fed to grid). Then take another reading a week, month or year later. Subtract the latest figures from the first ones for each reading and you'll have 3 numbers: kWh generated, Kwh taken from grid and Kwh fed to the grid. Then do the following equation:

Kwh used= kWh from grid + (kWh generated-kWh fed to grid)

Power use is very seasonal so to get the most accurate figure get a year's data. Now on to generation:

Perth is probably the best place in the world for PV generation since we get an average of 8 hours sun a day (it sometimes amazes me why there aren't panels on every roof!), so we are lucky in that respect. PV systems usually over perform in their first year, so there's no surprise that year 1 was our best year. The interesting thing is that year 3 was better than year 1. Most PV systems lose efficiency as they get older, so I was expecting this to happen with ours. I think it shows that the weather we've had is probably masking the PV cell efficiency drop off. We've had a very dry year which obviously leads to less cloud cover and higher solar radiation.

We now take weekly readings of gas and water consumption, kms travelled by car and cargo bike and also egg production. So stand by for more geeky installments. Embrace your inner nerd. Geek, c'est chic.

Saturday, May 7, 2011

Home is where the heart is

We just got home a from a holiday in mid north NSW. Blog worlds collided in the real world (Potato Bug) as we went to visit our good friends who moved there from Freo to become self sufficient, sustainable farmer, hillbilly types. It was lovely to reconnect with friends and see how they have fitted so wonderfully into their new life. They are very happy and we are very happy for them (though we still miss them so!). They converted an old dairy into their home and have two calves, chooks, ducks and a veggie garden so far (plus an orchard in the planning stages).
There is heaps of space for the kids to go crazy
and have wicked bonfires that I hope they will remember forever.


We seemed to have lots of time for tea drinking, walking, gardening, knitting and easter pinata making (it's the old double headed rainbow coloured easter bunyip we all know and love, of course).

The property borders state forest


So you will forgive us for contemplating packing up and moving to eden!

In many ways it was a very confronting and confusing holiday. We were constantly weighing up our suburban life to that of our friends and wondering how far they will be able to take their dream and indeed how far we will be able to take our dream of sustainability in the burbs. The main thing they took into account was the fact that the area is predicted to get wetter, while Perth is predicted to get dryer. We did notice a fair bit of wetness, growing and general greenness about the place. Our friends have some challenges too; they have frosts, as well as problems with fungal diseases on their veggies, clay soils and long weekly commutes in to town for supplies.

Here in Perth we are limited by water, sandy soils and on our block we are limited by space (I really do want goats Linda Cockburn style, but this will take some serious lobbying to Adam as well as my neighbours whose garden I will need for said goats). But even so, we really don't know our limits yet.

The more I think about what we want to achieve here the more I see we are limited by time. We could be much more effective gardeners, chook breeders, soap makers, bakers, preservers, aquaponic-ers, composters, cyclists, house refitters, bee keepers and all round super dooper good guys if we had more time. As it is Adam works full time and I'm part time. Eventually we hope to both work part time or less  to free up time for new skills. As for space, well, we have a new and cranking community garden that is about to start work on an orchard and our whole front garden is natives which we could convert to food production. As for water, we have not installed an approved grey water system yet (this is next on the list) and with more time we could water more effectively, use shade and mulch more thoroughly.

So maybe it is just a case of the grass is always greener. But on the other hand, maybe I'm just too emotionally attached to my home to see clearly. I missed my bike and my bellydancers. Home is where the heart is. And thankfully it rained the day before we got home. How wonderful.

And yes, we all had a great Easter!