Solar power in winter - there isn't much of it

Since the 1980s I've been experimenting on and off with small scale solar power. I first bought about 1/2 a square metre of unsealed glass PV panels from an electronics surplus store in the UK. These worked quite well for several years, producing about half of their rated 12 V / 200 mA on a good day. However by the time we emigrated the output from them had dropped quite a lot so I gave them away to another experimenter in Cambridge on freecycle.

The output of the original panels had dropped in part because this is what happens with solar cells, but it was accelerated a lot because they were not sealed and they had got damp, I'd already bought another solar panel, a 12 V 28 W sealed panel from Maplin shown in the picture to the left, to supplement their output. This came with us to the Netherlands, but for three years after we moved here, it was in a box in the garage.

A few days ago I finally got it out and put it on the garage roof - flat as you see it here to try it out initially - and ran a wire into the garage. I then measured the open circuit voltage at the other end of the wire, about 18 V, and then I hooked it up to a 12 V 20 W halogen bulb in the garage. Nothing happened. Measuring, I find that there is about 0.09 V across the bulb, and the bulb itself has a resistance of 1.2 ohms, so I'm getting a mere 75 mA at 0.09 V from the cells. That's 0.007 W. That's almost nothing. Around 0.02% of the rated output.

My initial reaction was to think that the panels have a bad contact somewhere. That the bonding of wires inside is no longer good. Then I thought a bit about where the panel is located right now. As you can see, one of our neighbours has a good sized tree at the south of our garden which casts a shadow. Also, it's quite overcast weather and of course the panel is not oriented well either. While manufacturers often claim their products will work "in any light conditions" and such like, actually they need very strong sunlight to achieve full output, and it's surprising the extent to which the output is reduced by such things as what looks to a human eye as only partial shadow.

On a brighter evening a couple of days ago I held up the panel to the receding sun and measured about half the rated output, which is probably as good as can be expected at this time of year. However, unless the neighbour cuts their tree down, I don't think I'll ever generate much from a solar panel at this position, except in the summer when the sun is higher in the sky.

I also have a small solar panel on my Mango to keep the battery charged. I built a small charge regulator to go with this, as even though its potential maximum output isn't huge, it could still overcharge the battery on a good sunny day (I've also built similar regulators, but capable of dealing with more current, to work with dynamos on Mangos).

In the summer, I rarely had to use my mains electricity battery charger. Even though the orientation of the panel is never perfect due to it being mounted flat on top of the Mango, the solar panel normally provides enough current to keep the battery charged. You perhaps won't be surprised to hear that it is just about completely inoperative in winter...

Sadly, Freecycle had some problems recently so for similar ideals, you're probably better off looking here.

New glass

One of the oddities of our home in the Netherlands is that while the ground floor was almost entirely double-glazed, the first floor was not. This was apparently the building standard of the time it was built - 1972.

The windows are large in our house, so they're more important than they might be in a house with smaller windows. However, the rooms without double glazing are those upstairs which we don't really need to keep particularly warm.

For some time we've been weighing up the pros and cons of spending money on glazing for rooms which don't necessarily need to be kept at a particularly high temperature, and eventually made the decision to go ahead with the work.

We were influenced more than a little by a study about the effectiveness of HR++ glazing which gives some figures suggesting that the HR++ glass is particularly effective. Also, the cost was more reasonable than expected (the second company we asked have a quote which was less than half that of the first), and as it was possible to replace the glass within the same hardwood window frames and not have to replace the frames as well (we're not huge fans of PVC windows), we decided it was a good idea.

We don't expect it to make the same big difference to our heating bill as cavity wall insulation did, as the thermostat in the house is downstairs and relatively unaffected by the temperature upstairs. However, it will presumably mean the entire house is better insulated so have some effect on the ground floor as well, and of course it also means the end of condensation on the bedroom windows, which froze on the insides in the winter and made it difficult to open the windows.

Yesterday it happened. New glass in the first floor windows.

We're hoping this makes conditions a little more pleasant for our teenage daughter in the front bedroom, which due to receiving least sunlight was the coldest room in the house in the winter.

So far, our heating bills have been lower each successive winter since we've lived here, as each time the house is a little better insulated than the previous winter. It's a pattern I'd like to continue.

Read more about the many things we've done to improve the energy efficiency of our home.
 

Sea defences

The Netherlands is a country within which a large proportion of the people live below sea level. What's more, some of the land was reclaimed from the sea. The world's largest artificial island has hundreds of thousands of people living on it, spread between three cities and several villages.

The sea defences here are quite incredible. They are built on a huge scale. For instance, the world's second largest moving structure is just one element of the defences which protect Rotterdam.

The video above shows the Aflsuitdijk, which I cycled across last summer. This is one of the major parts of the sea defence for the northern part of the country, a 32 km long dyke. Until very recently, this dyke which was built in the early part of the 20th century was the longest in the world.

In the wake of Katrina, the US has been urged to copy the Dutch system, which is designed to cope with one in 10000 year events rather than the once per century events that the US flood defences are designed to cope with.

Update: A few days later I learn that one in six British homes are at risk of flooding. Apparently, doubling the funding for flood defences to 1B pounds per year could save a cost of 4B pounds a year due to flooding. This could perhaps be seen as good value for money...

In the time we've lived here there have been many stories in the British press about homes being flooded. Not so in the Dutch press.

You can read more about the sea defences at the delta works website.

Making videos

This blog post dates from several years ago before I discovered that FujiFilm's guarantees are completely worthless. Do not buy FujiFilm products because if it goes wrong, the company will not back up their guarantee.

A few people have asked me how I make my youtube videos. I hadn't really thought about this too much, as I just do what I do. However, there is interest so I've decided to document it here.

I use a Fujifilm A210 camera. This is a five year old 3.2 million pixel camera which you'll have problems finding these days. However, it's no loss, I dare say that almost anything else from the same manufacturer, or any other manufacturer, will perform at least as well these days.

The videos are at 320x240 resolution and just 10 frames per second. The camera will only take 1 minute of video at a time, though I can take a lot of videos like that on the 512Mb xD storage card that I use with the camera.

There is no microphone, so all videos are silent as taken. I always hold the camera in my hand as this gives a shock mounting effect and while I like the effect that others achieve with rigidly mounted cameras I prefer this effect for my videos. I don't wear a cycle helmet, so helmet mounting wouldn't work.

My computer is now quite an old machine with a 1GHz AMD Athlon processor. Almost anything you buy now will be quicker. I use only open source software, and my computer runs Ubuntu Linux.

Video files are copied from the camera and I join them together with a command line tool called avimerge. I then chop bits out again with a tool called avidemux. If I'm adding audio then that is edited with audacity and turned into an MP3 file which avidemux can combine with the video. The music that I use is either played by friends, is out of copyright or is licensed in such a way that it is legal to use without paying royalties (creative commons, for instance).

I then upload that to youtube and use the youtube annotations feature to add captions.

If my videos look a bit different to other peoples, it's probably because I make them in a different way to some other people. There is nothing particularly special going on, though.


The still photos are also made with the same camera. I edit the photos using GIMP - a very powerful image editor which is again open source and free of charge.

One of the things I especially like about this camera is that the photos seem to have pretty good colour accuracy and reasonably low noise. Many digital cameras that use CMOS instead of CCD imaging chips seem to suffer in this way as a result (most mobile phones have washed out colour for much the same reason), even some which are newer than this one.

I've also made some videos by using an old 8 mm analogue camcorder, analogue mixer to add sound and (VCR style) DVD recorder. However, this is very time consuming compared with using video directly off a digital camera, and the results are not overly impressive.

At the time of writing my camera has taken well over 10000 photos and videos. It has travelled with me for thousands of kilometres, often dangling from my arm in all weather. It looks rather beat up now (click on the photo above for a bigger version), complete with the end being slightly melted by a battery which caught fire in my camera bag, but I know how to use it, I am very happy with it and won't change unless I have no choice.

Update Jan 2009. So I changed my camera... A friend sold me his second hand Kodak Z712is, which I have to say does make much better photos and video than the little Fuji. You can compare similar material shot on both cameras: New vs Old. However, I still use both. The little one is easier to carry and (probably) more robust. Also, the batteries last much longer in the little Fuji. Don't take this comparison as being anything absolute against one company or the other. Both companies (and other companies) offer cameras with similar features at different price-points.

You can find all my youtube videos here.


Some of you have probably noticed that my camera didn't take its own photo. We also have a Fujifilm A205S. Exactly the same camera but just 2 M pixel resolution. Some of the photos on the blog are taken with that one, and a very few are taken with my mobile phone.

Later in the 21st century update
Of course, everything above is now outdated. Lots of people make youtube videos and they use many different types of camera to make them. HD video can be shot so inexpensively now that it's not very worthwhile to mess about with old cameras like those above. You do need something more powerful than a 1GHz Athlon to edit HD video, though.

My youtube videos have continued to grow in number and you can still find them all here.

We bought a later model of FujiFilm camera in August 2014 which went wrong in April 2014 and was returned to FujiFilm in May 2015. Though this suffered from a known manufacturing fault, the company would not back up their guarantee. Many people have had the same experience. I recommend avoiding FujiFilm products.

Cavity wall insulation effectiveness

Last year we had cavity wall insulation installed. This is the third house we have done this with, and for the third time it has been extremely effective at reducing the heating bill.

January 2008 had an average morning temperature (my measurement taken at whatever time in the early morning that I happen to have looked) of around 5 C. This winter has been the coldest for over a decade and the average temperature taken in the same way in January this year was -0.5 C. Despite this, the gas used was 281 cubic metres this January vs. 274 last January.

I didn't write down the temperatures for December 2007, but remember that the lowest temperature I cycled in was -6 C vs. -11 C this winter. However, our gas consumption was 396 m^2 in December 2007 vs. 298 m^2 in December 2008.

Overall this seems to have been a very effective measure once again. It looks like even though it cost us around 700 Euros to have the insulation installed, it will pay us back in about three years. It's much cheaper to have cavity insulation installed in the UK, so the payback period is even shorter there.

We still have more to do here to get the heating bill as low as we'd like, though.

On the right, another photo of the frozen canal taken yesterday. It snowed a little. The snow was quickly cleared from the cycle path, but rested on top of the frozen canal. I wonder how much insulation the house boats have.

Further updates
Since this blog post we've installed far more insulation and our use of energy for heating is much reduced as a result, along with the cost of energy.

Read more about the many things we've done to improve the energy efficiency of our home.

Carbon Neutral

The clip is from our local paper. Assen has planned for some time to become carbon neutral, and progress towards this aim continues. The first paragraph reads "Assen most remain an attractive city for future generations. By 2020 the government will be carbon neutral. CO2 output will be taken care of by a forest in the city and in Indonesia."

Now I have to say I've always been somewhat skeptical of the benefits of planting trees to absorb carbon dioxide. The problem is that there is only so much that one can do. Whatever way you look at it, we can never return to the state that we used to be in, when there were more trees on the earth and the fossil fuels were still locked up underground.

However, there are some very good policies which form some of the rules which the goverment will be adhering to:

1. Stimulation of more use of bicycles (already used for nearly 40% of all journeys) and public transport, not only by the government but also by city residents.
   
2. Five hectares (twelve acres) of woods are being planted this year in the city and the city will also support the Borneo Orangutan Survival organisation in providing woods which double up to absorb CO2.
3. Vehicles are being converted for natural gas and biofuel (I'm also less sure of the benefits of these)
   
4. The government uses electricity 100% from renewable sources, and is looking into "green" gas supply.

Many traffic lights in the city are already LED devices. What isn't mentioned in this article is an attempt to reduce energy consumption by converting street lights to use LEDs. I covered this before on my other blog.

If you are interested in this subject you may also be interested in the considerable effort put into recycling.

Photos of the cold weather

Yesterday it was -6 C ( 21 F) and the canal was just about completely solid.
This morning it was -10 C ( 14 F ) and completely solid. So much so that people have been able to skate on it.

It's much the same for all the lakes around this area. No snow as yet, but a very heavy frost.

All the bike paths are kept clear of ice, though.
Icicles on our windows have grown to about 40 cm long.

This hasn't stopped people going out, of course. In fact, it's given them new things to go out for: