My House Sketch shows evacuated-tube solar-thermal panels along the bottom of the south roof. An offer came up which would save at least £1200 relative to possible alternatives so, with a bit of prodding by skyewright, I ordered them the other week and they arrived on Tuesday. I had to have a play, of course.
More...Last autumn I wrote a post on the Navitron forum about a reason for cooling of the stratosphere with increased carbon dioxide in the atmosphere. I later posted a reference to it in a comment on Kaitlin Alexander's blog (Climate Sight) which lead to further discussion which showed that what I described is only one of the mechanisms which tends to cause stratospheric cooling. In particular, Martin Vermeer's comment explains the other, perhaps the main, mechanism well.
Nevertheless, I'm sufficiently smug about my own explanation that I'm going to put a slightly-edited copy here.
More...As mentioned in a previous post I have a few small PV panels out in the garden feeding an old battery via a Morningstar TriStar MPPT 60 charge controller. With the experience of playing with this controller I'm having some second thoughts about how worthwhile MPPT still is as PV panels get cheaper.
Hearing of two of these failing in a short time also helps to undermine my resolve.
More...My previous entry, PV, ETs and Flatties, compared the outputs of various solar panel types by price. If, like me, you're designing a house to have a large south-facing area for solar collection then this makes sense as price is the key factor. However, if you have an existing house which is not designed with solar collection in mind then area might be the limiting factor. Following a request by Wookey here's a similar graph normalized by area.
More...The overview of my house plans (at House) are a bit out of date. The design has, as you might expect, evolved a bit (and is still evolving) and it never seems like quite the right moment to bring it up to date. That's one of the points of this blog: a blog post is only supposed to be right on the day it was posted; etiquette says it's “cheating” to later update an entry in more than the most trivial editorial ways without clearly marking what you've done.
Anyway, here's a quick sketch of more current thinking.
More...Following on from my previous PV For Space Heating post, it's interesting to consider what combinations of photovoltaic (PV, electric), evacuated-tube (ET) and flat-plate (thermal) solar panels make sense, particularly for the provision of space heating and domestic hot water (DHW) for any significant proportion of a winter not close to the tropics. First, a look at the performance of these panel types.
More...Using photovoltaic panels to generate electricity to heat your house is nutty. Still, as the price of PV steadily drops (mainstream panels are now available at around £1/watt, including VAT) it's instructive to keep an eye on just how nutty it is.
More...Not surprisingly my solar warm air panel isn't doing a lot now it's December so perhaps an update would be good.
More...Dear Company X,
You want me to get my statements electronically. This is quite understandable; it'll cost you a significant amount of money to print and post statements which must be a bit irritating when you're already running a website for me to access my account. And moving bits of paper around has some ecological impact which would be worth avoiding.
But, sorry no, I always resist if I possibly can.
More...The other day somebody asked on the Navitron forum about batteries for off-grid use specifically mentioning the use of lithium-ion batteries. My reply encapsulates the beginnings of my thoughts on the subject well enough and, unlike most forum posts, stands alone well enough that I thought it was worth re-posting here with some light editing.
More...The other day I built a Nanode so needed to re-jig my network wiring to be able to test it conveniently on the workbench in my office. In the process I needed to reset my Wifi router (forgot the admin password - oops). After that I found my laptop was horribly slow communicating with the big wide Internet.
More...On Sunday afternoon I went for a short walk up the hill behind (to the west of) a house plot I'm contemplating. Here are a few pictures - click to embiggen.
More...The other day I bought a Pogoplug to use as an always-on home server. I had no intention of using the official software at all but rather planned to install Debian GNU/Linux immediately. In the process I found a little gotcha not mentioned in the otherwise-excellent instructions (alternative) I was following, quite possibly because it's new behaviour implemented since those were written.
More...Somebody asked me about using EW Windows Uploader with a USB-to-serial adapter when running under Linux (with Wine presumably). My reply might be of sufficient interest to others to be worth posting most of it here.
More...We're coming up to the end of the last Space Shuttle mission. There's been a lot of agonizing about this being the end of US human spaceflight. Similarly, there's been a lot of wailing about the possible cancellation of the James Webb Space Telescope and the general disarray of NASA's programs over the next few years.
Frankly, I think this is all a bit misguided.
More...There was a lot less breeze this morning but still very little heat being moved into the bathroom despite temperatures in the collector in the mid 30s °C and in the box outside the window in the mid 20s so I dug through my junk boxes for an old computer fan to hook on to one of my Maplin 15 W amorphous silicon PV panels.
More...The solar warm air collector is now at version 1.0. Previously: part 1, 1.5, 1.6 and initial results.
The weather has been pretty poor, though with a few nice days. Unfortunately, the nicest last week were Monday when I had a hospital appointment 40 miles away so all I managed on the solar warm air panel was to buy some more draft extruder strip and Thursday when I woke feeling very depressed and only got a little bit done - I slept most of the afternoon.
Consequently I got the box to feed the warm air into the bathroom window done midday Sunday, just as the sun was far enough round to the west not to be on the panel.
More...Saw this little critter in the front garden this morning:
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