Saturday 18 May 2013

Create a better environment... with this bag?

I won't name the shop. The message seems great. Not sure how much it will help. In terms of resources, the use-your-own-shopping-bag mantra is probably myth. Polyethene bags use minimal resources, meaning that you'd need to use your bag claiming you're eco a few hundred times to be in the green in carbon accountancy. And don't forget the one you lost, the one in the car, and the other five you have in the drawer in the kitchen. 

Manufactured multiple-use shopping bags go through multiple processes and end up weighing much more, meaning more carbon getting them to the shop.

This one has a metal zip. Good old eco steel wrought at hundreds of degrees centigrade from iron ore dug from the earth, upstream from rivers of rust. OK, so it's only a few grammes of steel, but grammes of steel use kilogrammes of water and each kilogramme of steel is responsible for 4 kilogrammes of CO2.

They are a symbol for the consumer, and a lucrative product for the shop, making them money while making them seem green. At the risk of being cynical, the bottom line incentive for the shops to use them will be increased profit, not reduced costs. That means more CO2. Not that shops and business aren't trying to do the right thing, just that the economic system in which they work makes the right thing unlikely.

However, this bag is partly insulated, so will keep groceries cooler between shop and fridge at home, saving a little electricity. In this sense these bags are eco.

Talking of fridges, though, ours has had a problem and a guy has been coming over the past few weeks to fix it. The ice maker isn't making ice properly, and the last thing he said was that cold air is leaking through a hole up into the main fridge, which is causing ice to form there. 

Anyway, the good news is that they've decided to replace the Fridge. Newer fridges are more efficient, and it will no doubt have some extra functions.

At least this is good news for us. As far as resource consumption and the pressure on the environment from this, and the stress from another piece of white stuff that needs scrapping, it is another minor disaster. Number 14,000 for the day.

^Hickman, Martin (2011-02-20). "Plastic fantastic! Carrier bags 'not eco-villains after all'"The Independent (London).


P.S. Sorry the image at the top ended up on it's side. I'm not sure if it's worth my effort and the computer's processing power to rotate it.

Monday 13 May 2013

Rabid anti-solar propaganda: Exposed

PJ sent me a link to a graph showing the "almost Moore's-law-esque cost decline rate" of solar panels.


Well, it's certainly going down, but it looks suspiciously linear, at least in the projections from 2013 to 2020, while Moore's Law suggests exponential decline (halving in price, doubling in power every eighteen months). It's not clear where the projections come from, but there's more information here, from the same writer.

This graph came from an article about research from Citi Bank: "These 10 Technologies Are Completely Changing The World". Solar was number 10. I felt immediately that it was put at number ten grudgingly. That the writer didn't really want to add it, but gave in at the last minute. It had e-cigarettes as the number two "disruption", which I struggle to believe will change very much at all. 

Above solar in the list were new ways of getting fossil fuels out of the ground, and switching from oil to gas in vehicle fuel. Fracking is not going to completely change the world, I hope. It'll leave some pretty big scars on it, but in terms of the precious economy, all it will do is is leave the tap running longer. 

One glimmer of sunshine was a factoid in the comments that 75% of young people would give up their car rather than their smart phone. The source of this is unclear, though the commenter thought he'd seen it in the LA Times.  

As well as solar being put to the bottom of the list, the language was dripping with derision and angry denial.

Quote: "Solar can even be viewed as a "parasite," stealing demand from previously installed generation."

How terrible. Nasty solar taking away that demand for those poor suffering thermal power stations. Robbed of their opportunity to burn coal and send all that lovely carbon dioxide into the air.

Then it has this bizarre quote: "
As solar gets cheaper, it will be possible to use it when there's less sunlight out." 

How is the cost of solar going to make it work when it's less sunny? Like, is a car going to go faster if the price goes down? What they actually mean is that as solar gets cheaper, it will become financially viable to install in climates or situations with less sunlight. Wouldn't it be great if journalists understood what they were writing!

It goes on to quote Citi bank: "Its nature means that the technology keeps getting cheaper, while alternatives gradually become more expensive, and so the 'problem' only becomes exacerbated."


And why is it a problem? I can only speculate, but here are a few ideas:

1. Human existence is only complete if we can drive cars whenever we need to move more than a few metres. Cars, to be real cars, must be filled up with petrol, must be run by engines that cause several explosions every second, and must send noxious gases out of the exhaust pipe. The exhaust gases are essential because they may be needed for poison in an emergency. Solar power threatens denying us this basic human right, cutting off our oil supply and forcing us into vehicles that are quiet, and free of fumes from evaporating benzene at the filling station to oxides of carbon, nitrogen and sulphur leaving a trail behind. Or to actually use those things hanging below our arses called "legs".

2. It's a Chinese plot. As we know, most solar panels are made in China. Or Japan. Or was it Hong Kong? No it's definitely China. Could be Korea though. Anyway, it's definitely not America. Or Britain for that matter. Old oil companies are not making money from them, as they would be from oil coming from all those middle-eastern countries that we've been spending so much time and effort invading over the past few decades. Those nasty foreigners are flooding the market with cheap products, and capital is flowing out of the west to buy them up. It's just not fair. 

3. Sun worship is a pagan trait of Zoroastrians. It is offensive to all Christians, and should be guarded against. Solar panels are not innocent generators. They are evil symbols of solar worship. They are miniature temples to Zoroaster and as they spread, the future of Christianity is at risk. They are literally taking over, from our roofs down and soon people's faith in Jesus will be shaken as they realise that it is the Sun that is all powerful, that is giving us life, light, hope, and reductions to our electricity bills and possibly even grants or tax rebates. 


Read more here: www.businessinsider.com

Tuesday 7 May 2013

Three miconceptions about solar power

1. You'll lose out in the winter.

There is certainly less sunshine in the winter, since the sun spends more time below the horizon and more above the horizon in the summer. Also the sun is higher in the summer, which means a less acute angle to the atmosphere, less air to get through, and stronger rays reaching the earth. Also, depending on where you are it can be more cloudy in the winter and more sunny in the summer. So there's less solar radiation available for electricity in the winter. On top of this, in the winter you tend to use more energy, so there will be less left over. 

However, a major factor in generation is the angle of the panels. The steeper the panels are, the more of that winter sun they are going to get. Typical roofs in Japan are too shallow for good winter generation. 35 degrees is optimum for year-round generation. Slightly higher will generate more in the winter, and a little less in the summer. 

As we go into the second year, you can see our generation below. The orange line is the manufacturer's simulation, which so far we have out-generated by 5 or 10%: 

March was our third best month so far. December was the worst month, but the panels were still generating. 

2. You can't store the electricity.

This isn't a misconception. This is usually the truth. But many people have the idea that you can get solar panels, get a battery that will store the electricity they generate, then you can use your own electricity when the sun is down. You could do this, but batteries are expensive, they are not very efficient, and financially you're better off selling electricity you generate to the grid and using electricity from the grid when you need it at night. Looking at our yearly averages, we generate roughly twice as much energy as we use (36 kWh/day compared to 17kWh/day) but we earn about six times more cash than we pay (45,000 yen coming in each month and 7,500 going out, on average). So I'm not rushing off to buy a battery right now. 

3. The government is paying artificially high prices for it.

The government is certainly subsidising people who put solar panels on their roofs by offering grants, and is forcing electric companies to subsidise them by paying a high price for solar electricity with a feed in tariff. However, I'm not sure you can call this artificial. This is a government investment in infrastructure that will be contributing to energy generation and making up part of the electrical jigsaw of the future. 

Especially when you consider how much is spent on other energy technologies. You don't think private companies set out to develop nuclear power stations on their own, do you? And what about tax money going to building gas, coal and oil power stations? I've been looking around for the answer to my question: how much tax money is spent on energy? It's not immediately obvious, so here are some random factoids instead, from world-nuclear.org

Based on 2005 data, 40% of the world's R&D spending on energy is made by Japan. Most spending is going on Nuclear fission. Spending on energy conservation, fossil fuel R&D and renewables R&D is similar. A little less is spent on nuclear fusion R&D. 

At the moment, solar is an expensive way to generate electricity, but all technologies begin expensive since you're paying for research and development, and manufacturing infrastructure. We've had 150 years digging fossil fuels out of the ground, and have become very efficient at doing that. In fact, a lot of spending on energy efficiency ends up making us better at using energy. The first uses of steam engines were pumping water out of mines, which made it easier to get coal out. So the cost of those fossil fuels is artificially low and nobody is doing anything to replace them. Economically it's the same as clearcutting forest and selling the wood without doing any replanting, only much worst because you'd need a time machine to go back millions of years to replant. Nuclear power has its own issues that I won't go into here.

So subsidies of solar power, rather than artificial, seem sensible and far sighted, especially for a country that produces solar panels and will benefit from demand. It's not such a big deal paying out a few hundred thousand yen here and there to help people put some panels on their roofs, that will generate electricity for the next half century without any need to import leftovers from other country's nuclear bomb factories. Although I don't want to get too political or emotive and I would like to have some more solid statistics to base this on, and know how much the returns on solar power are compared to the investment, and what the real costs of everything are. 

4. There are lots of solar cowboys out there. 

This is not a misconception at all. The people putting on your panels may be much more interested in getting cash from you, and you getting a grant from the government that will go straight to them. They will be less interested in how much electricity your panels generate over the next half century. 

The price of freedom is eternal vigilance, and in the kingdom of the sun blind, the guy with very dark sunglasses is king. 

Thursday 2 May 2013

The right level of humidity

I found something more precise on humidity levels from Justin O'Keeffe's blog.
It looks more precise, but the reproduction leaves a bit to be desired. It's a photo of a poster from a presentation, by the look of it, but I can't find the original source online.

There was one here: https://www.educate-sustainability.eu/portal/content/factors-comfort
There's another more sketchy one here in the green garage, Detroit, with the temperatures in Farenheit. I know I'm prejudiced, but I don't trust temperature scales based on the body temperature of sheep, when there is a perfectly good one based on the freezing and boiling points of water. Biology is at least two steps down the fuzziness ladder in the realm of the sciences, and physics should not be borrowing measurements from there.

There's another one here.

During the one-year evaluation, the boss's son from the builder said we should aim to keep it between 40 and 60%, although he didn't have anything more scientific, and for more precision told us we should see how dry our skin and throats feels. I asked where the humidity should be as far as the wood is concerned.
The architect then started talking about wood having 8-10% humidity, so the humidity of the house should be fine.
I researched more about this later, and found that he was actually talking about the moisture content of the wood. This is not the same as the humidity.
The thing they have in common is that both are percentages.
But the percentages are very different. The moisture content of the wood is the amount of the weight of the wood that is water. The relative humidity is the amount of moisture in the air, as a percentage of the maximum moisture that the air can hold.
Obviously there is a relation between the two, since wood is somewhat permeable and moisture can get in and out.
Here are some relationships, extrapolated from woodweb.com.
22% RH = 5% EMC
28% RH = 6% EMC
35% RH = 7% EMC
42% RH = 8% EMC
49% RH = 9% EMC
57% RH = 10% EMC
65% RH = 12% EMC
74% RH = 14% EMC
80% RH = 16% EMC
EMC is the equilibrium moisture content. In other words, the moisture content that you'll end up with if you leave wood in conditions with that relative humidity.

They give a short version too:
RH%  EMC%
0 = 0 
30 = 6 
50 = 9 
65 = 12 
80 = 16

Changing the moisture content of the wood will make it shrink or expand, so if it is supposed to stay between 8 and 10%, then the relative humidity needs to stay between around 40% and 60%. Or if the relative humidity of the building stays between 40% and 60%, that's what the moisture content will be. I don't seem to be getting much nearer finding definitive recommended humidity, but I'm still recording it in my house and within the walls, where the humidity has been averaging 36% and fluctuating between 49% and 23% over the past two months, with an average temperature of 15 degrees.

I can see some kinds of trends in the humidity within the walls, with some differences between the North and the South. Back in July the middle of the north wall was averaging 58%, fluctuating between 51% and 68% at an average temperature of 27 degrees. Over twenty days in the middle of February it was averaging 31%, fluctuating between 23% and 40%, at an average of 11 degrees.
In the South wall, the July humidity was slightly lower with slightly larger fluctuations. In both May and October, the humidity in the North wall was around 10% higher than the south wall. Roughly averaging 50% against 40%.