Sunday, February 28, 2010

Down with Uplighters

Up-ligthers have, probably quite rightly, a reputation for being a very inneficient form of lighting.  I thought I would share with you a 1 hour project I undertook last year to radically reduce the carbon footprint of our humble up-lighter.  As we live in rented accommodation we were not keen to spend huge amounts of money on light fittings for our forty square meter lounge.  Instead we bought ourselves a dimmable halogen up-lighter which provided a nice light that could change with our mood and which we could take with us when we moved.  Being a large room we had to have quite a powerful light and the up-lighter we chose used a 300watt halogen bulb.  We use it virtually every evening for 3-4 hours so it probably accounts for 10% of our lighting bill single headedly.

In September last year I was walking through our local DIY superstore when I spotted some GoVenA 20W dimmable compact fluorescents on special offer and immediately got the idea of replacing the halogen bulb with two of these.  [I should say at this point that I am a qualified electrical engineer, but I don’t think that this kind of project is particularly difficult for an average Do-It-Yourselfer with reasonable knowledge of electrics].  In the same store I was able to purchase two bulb holders that came with a screw mount. 

Once home I disconnected the lamp and started to remove the halogen fitting. The up-lighter sits on top of two twisted copper tubes (see above picture). One tube carries the live and the earth wires while the other carried the neutral.   The halogen lamp was strung between them.  Luckily on the fittings there was a screw fixing for part of the halogen lamp assembly which I could use to mount the two new eddison screw fittings.  The only thing that remained was to take a live feed wire to the other side fitting and vice versa for the neutral.  The earth wire remained connected to the metal part of the lamp (see picture, right for finished assembly).  The whole exercise took around an hour and worked perfectly and safely. Actually, as it produces so little heat, its probably safer than the original [HOT!] lamp.

The twin 20W bulbs are easily as bright (if not brighter) at maximum brightness as the 300W halogen was, but uses just 13% of the electricity.  If, as I assume, this one fitting consumed 10% of our lighting power, which In turn is 10% of the electricity we use and that is 20% of our total household energy consumption then I saved 0.17%1 of my total household energy consumption for a cost of around £40.  Better still the light spectrum coming from the bulb is cleaner and whiter than the original halogen bulb and the spectrum remains the same as the light is dimmed.  According to the GoVenA website the lamp can be dimmed to 2% of full power – or just 0.4W per bulb!  These bulbs are extremely efficient even compared to other compact fluorescents.  FYI I found two YouTube videos of a similar bulb here and here.

Sunday, February 21, 2010

What You Can’t Measure, You Can’t Control

The commitment made by 10:10 members is to reduce their carbon footprint by 10% in 2010. This is a very small fraction of the 80% reduction we are told we need to stop global warming so surely it should be possible? But is it so easy? To answer this question we need to apply science, not emotion.
There has been a huge rise in obesity over the last 40 years. Scientists have been looking into this to try to understand why. Most people intuitively link it to the rise in processed “fast” food consumed at home and in restaurants but scientists have found that our daily calorie intake has not significantly changed in the last 40 years. They did, however find a strong correlation between obesity and car ownership. Moreover, the increasing use of cars has led to the demise of the corner shop and replacement with out of town supermarkets such that it is now almost essential to own a car. If it is lifestyle change that is causing the rise in obesity and not our calorie intake, it’s no wonder that most diets don’t work.

We should conclude that a “carbon diet”, like any other diet, will only work if we make significant and permanent lifestyle changes.  Unfortunately as any dieter knows, those diets that include [perceived] depravation or take significant physical or mental effort are very difficult to stick to.  Currently the UK Government is urging its populous to drive “5 miles less per week”.  While the aim is laudable we first should ask “5 miles less than what?”; i.e. how do we know if we are doing it? Counting miles is like counting calories; it’s too hard to do so it won’t work for the majority of us.  Secondly there is an implicit assumption that many journeys are simply not necessary. For most of us going to work, going shopping etc are necessities.  In reality the car is a means to an end, not an end in itself and to affect a cure you have to tackle the disease, not just the symptoms. For instance, according to my brother in law, Professor Gareth Edwards-Jones, half of all so called “food miles” are down to car journeys to and from superstores.  Perhaps the Government should be promoting on-line grocery shopping as a concrete way of saving a trip to the superstore rather than some vague, inaccessible (because it is not measurable) 5 miles per week?

But surely there is a quick fix? Wind energy, solar energy and other renewable energy sources are all laudable goals to pursue but it’s not clear to me whether the whole life-cycle [carbon] costs of some of the proposals are actually higher than the ones they replace. Take the Government car scrappage schemes for instance. While it is clear that new cars produce much less carbon per mile than older ones, how much carbon is produced in making that new car? and how many years could you run the old car on the equivalent carbon saving? Let’s assume that the carbon cost of producing the new car is the equivalent of 1 years fuel consumption.  I have no idea whether this is correct but it sounds reasonable.  Let’s further assume that the new car produces 25% less carbon per kilometer than the old one.  The break even point of the new car would then be after 3 years, by which time the old car would be 13 years old and would probably be scrapped anyway.  I suggest that the car scrappage scheme was more about helping the economy than reducing our collective carbon footprint.

Low energy light bulbs are a clear win-win but even here the actual carbon saving is hard to measure.  According to a BBC article lighting accounts for 19% of global electricity generation, though it does not cite a source. Other sources more targeted towards domestic electricity consumption put this figure closer to 10%.  A quick web search would show that electricity makes up only 16% of the total energy consumed in an average European home.  The consumption of energy in the home is roughly 2x that consumed by the family car(s).  Low energy bulbs save around 75% of electricity.  Replacing all lights with low energy lights would therefore result in a total carbon saving of 10% * 16% * 2/3 * 3/4 = 0.8%, a worthwhile saving, but hardly a magic bullet.  Perhaps less well known is that you could save as much energy by changing your 10+ year old refrigerator to a modern A+ rated one, or even changing your 20 year old central heating pump for a new one.  It is these things, thac consume power 24/7, that are the real electricity hogs.

While many of us know fad diets are doomed to failure, the lack of published (or should I say publicized) science about carbon reduction leaves many of us clutching at straws.  There is a clear need to lower our carbon footprints, what is less clear is how we can achieve it.  We need tools to measure, not Government platitudes if we are to make lasting, positive lifestyle changes. This to me should be the central lobbying effort within 10:10.

Saturday, February 13, 2010

Step 3: To insulate or not insulate, that is the question?

We rent a fairly typical medium sized (200m2) Belgian detached house.  Built circa 1970 it has uninsulated cavity walls, concrete floors and ceilings, first generation double glazing and no insulation in the loft.  The house has been rented out for the last 15 years or more and belongs to a retired German gentleman who lives up the road and used to work for the EU. 

In 2008 Electrabel in Belgium hugely increased its gas and electricity prices and put our standing order up to a crippling €420 a month so we approached the landlord to ask him about insulating the house.  At first he was not interested, after all what would he gain from spending the money?  It was not until we threatened to move out that he finally decided to look into it.

As an engineer I compiled a detailed heat loss analysis spreadsheet in support of my cause.  The heat loss at 0oC was a staggering 16.4kW.  I calculated that by insulating the walls and the loft this could be reduced to 7.7kW which would save us around €180 a month.  I was so sure of my figures that to sweeten the deal I offered to pay €500 to the landlord towards the cost.

After some research my landlord decided on the company he wanted to use and got a price of €5600(!) before subsidies.  Electrabel gave a subsidy of 20% and there were other grants available.  There was, however, a problem because most subsidies in Belgium come in the form of tax relief against earnings whereas the landlord paid his taxes directly to the EU.  Fortunately as a German our landlord was very thorough in his due diligence and he eventually got the subsidy up to about 50% and the decision was made to go ahead.

By this time it was winter and the elements were not kind to us.  We had a prolonged cold snap of -11oC and our huge gas boiler was struggling to cope.  Worse the insulation could only be injected when the temperature was 2oC or above so we had to sit it out.  We bought some logs and often lit a fire to help the central heating cope. On the 29th January 2009 the weather was at last warm enough for the work to be carried out.  The concrete floor of the loft was coated with 6cm-8cm of hard insulation foam.  The surface undulates a bit but is hard enough to walk on.  The walls and bedroom ceilings were immediately warmer to the touch and the house felt much warmer with fewer drafts.

One year on our standing order has been decreased to €290 a month and we expect it to go down even further the next time the gas meter is read.  We have already saved our €500 stake and are now into profit.  In absolute terms the full cost is recuperated in less than 4 years.  We were lucky that we were able to convince our landlord that it was a good investment.  In my opinion the Government should oblige all landlords to insulate their rental properties to the highest practical level. They should also allow people equal access to subsidies whether they are tax payers or not.

Saturday, February 6, 2010

10:10 Carbon saving tips: Step 2 - Reduce, Reuse, Recycle!

After 15 months the company I came to work for in Belgium was closed and I lost my job. This meant having to give back my company car and for the first time in 20 years meant we were down to being a 1 car family!

I managed to do some consulting work to keep a little money coming in and this led to a contract with a small firm in Brussels. By this point our savings were running low and we still did not feel we could buy another car. Luckily about a mile from home there is a tram that costs only €1.25 each way and takes me to within 100 meters to the office.

Good as the tram is, its main issue (like all public transport) is latency. I will explain: At the tram’s maximum speed, 60km/h, the 12km/7.5 mile journey would take 12 minutes. However including all of its stops the total time on the tram is 25 minutes. The Tervuren tram runs every 7 minutes during peak time. I have to change trams at Montgomery and the second tram, though nominally every 5 minutes can keep me waiting over 10 minutes if delayed by traffic. The worst case journey time including this latency is 25+7+10 = 42 minutes, instead of 12 minutes if it was point to point. The shortest journey is 30 minutes and the average 35 minutes. All of this does not include the 1 mile to get to the tram stop, which is a further 10 minutes. This was uncomfortably above my self imposed 30 minute commuting time limit.

For comparison, on the odd occasions I took the car it normally took 30 minutes. The shortest time was 18 minutes and the longest 2 hours 40 minutes (caught in Belgium’s biggest ever traffic jam with 500km of tailbacks across its motorway network). At least one in 5 journeys was over 1 hour.

As spring came I decided to try cycling to work. I’d bought quite a good Cannondale bicycle some years before so as to occasionally cycle to Ely and take the train into Cambridge. I had also cycled to Leuven a few times when the weather allowed. I was impressed that at 48 I could cycle to work in around 35 minutes. For about half of the journey I could take advantage of cycle lanes. I could overtake stationary traffic at junctions which kept my average speed up. Best of all the variance in journey time was low, with the best being 28 minutes and the worst being 40 minutes.

Unfortunately, the journey to work is almost never flat, with two long uphill drags and another two back down. The hill climbing dominated my journey time and I really had to push to keep my average speed up. By the summer I was reaching work in a dripping mess and had to take a shower. Showering added 15 minutes to my journey time and somewhat negated my gains. Nevertheless, the commute now doubled as useful leisure time and I was feeling the benefits of having an hour’s exercise every day so I did not want to give it up!

The answer to improving my work commuting times came in the form of an electric bicycle kit from Alien Ocean in Scotland. They sell electric bicycles from ₤500 but as I already had a good bicycle I decided to go for their Lithium Ion battery plus front wheel motor kit. It was very simple to install and in around two hours my new “electric bike” was ready. The kit, quite rightly, came with its maximum speed set to the EU electric assist limit of 25km/h/ 15mph. Although the assist increased my uphill speed from 6mph to 10mph I could already cycle faster than 15mph on the straight so the gains were a little disappointing. Happily the Alien Ocean kit is designed for both US and EU regulations so I was able, at my discretion, to turn it up to the much more reasonable US limit of 20mph. This probably means my electric bike is illegal but I figure if it means I can save the environment it is a transgression I would stand up for.

My journey time is now comfortably and reliably under 30 minutes. The motor is driven by a thumb throttle so I still get as much exercise as I want. On the straight I get a small amount of assist, perhaps 1 or 2 mph. On the hills the adjusted electric assist is closer to its maximum power of 250watt and has added another 2mph to 12mph. The 360WHr battery will just manage 2 days or 48km (30 miles) on a charge, which is lucky given I have forgotten to charge it overnight on several occasions. A days commuting costs just 0.2kWh/€0.03. Better still it meant we could comfortably run one car instead of two which is a massive saving in both cost and carbon footprint.

There is one word of caution however. It is more dangerous to cycle than it should be. I’ve been cut up by thoughtless car drivers on 7 separate occasions and actually collided with cars twice, once while I was in the cycle lane! If Governments really wants to promote cycling then they must do more to protect cycling from other road vehicles and, arguably, less to protect cyclists from themselves. In my opinion the 15mph limit makes the electric bicycle unattractive as a commuting vehicle; the Government should trust cyclists to use their discretion, after all they don’t limit cars to 70mph!

[The bike, including battery (back) and electric motor (centre of front wheel)]

Wednesday, February 3, 2010

I could not put it better myself ...

As the debate about whether climate change is happening continues to rage, here is a man who not only has my opinion on this, but manages to say it much better than I ever could.

Check it out for yourself!