The urge for less energy use

Frost heaving and cold bridge fixing in foundation wall

2011-10-14T19:16:00.003+02:00

Last fall we got a new big sliding door to our garden deck. During the winter we had problems opening it, probably due to frost heaving. Our carpenter suggested we should insulate the outside of the concrete slab that the house is built upon. This concrete is also a nasty cold bridge into the house floor. So I got the spade out and started to dig.

The concrete slab is about 50 cm ( 2 feet) deep, at least around the perimeter. I also removed the lower plank to make sure to expose all of the concrete.

Today it is common to add 5 cm ( 2 in) of styrofoam insulation to the foundation wall, so I decided....

...5+5 cm should be good. I think it is a good idea to add as much insulation as possible while at it. I managed to cover all the exposed concrete.

Then there is an issue of leading any water away. So I added some fabric, "Leca balls" and a drainage pipe.

Close it up.

I also added 60cm of 5 cm thick styrofoam from the wall and out. This will also help to insulte, and will later be hidden under the new deck that will reach all the way to the sliding door. All set for the winter! When it gets real cold, it will be interesting to compare inside floor temerature close to this wall to similar positions close to walls with no foundation wall insulation.

Summary in Norwegian: Vi har installert en stor skyvedør mot hagen i vårt rekkehus fra 1978. Forige vinter begynte den å gå treigt, antagelig på grunn av telehiv. Dermed gikk jeg i gang med drenering og isolering av betongplaten som hele huset står på. Hensikten er å unngå at det blir frost under denne, og å fikse den enorme kuldebroen det er å ha sementgulvet i stua koblet rett ut i kuldegradene utenfor. Isolasjon er ikke noe man skal spare på, det er bare å kline til med det det er plass til. Her ble det 10cm mot veggen og 5cm plate 60 cm ut fra veggen. Til sommeren kommer vår nye hage platting her oppå isolasjonen i bildet. Andre steder i hagen planlegger jeg å få hvertfall de 10cm mot muren. Gleder meg til å se hvor varmt gulvet blir der hvor det er ekstra utvendig isolasjon i forhold til der hvor det ikke er.

One hidden master switch for TV, PS3 and surround sound

2011-05-15T16:22:00.000+02:00

Kill your standby losses with a master switch.Below our TV we have a decoder, HDMI switch, PS3, Wii, and a sourround sound amplifier. First I tried to use a smart strip to turn off everything when the decoder goes into standby, but it was difficult to adjust the sensitivity, because the decoder used almost the same amount of current in standby as in normal use! So I simplified and made an easy to access master switch placed behind the TV screen (blue arrow). It turned out real good. The kids love it since it is much faster than using all the remote controlls. On an average day our family uses 1.2kWh on our entertainment centre. Our plasma screen uses about 170W on an average bright picture when set in standard display mode. When set to dynamic it uses almost twice as much. So keep the brightness down, and turn everything completly off when not in use.

Insulate inside walls step by step

2011-01-01T21:14:00.016+01:00

Our wodden house from 1978 has only 10cm (4") insulation. This winter I decided to add an additional 10 cm of insulation to the inside of the wall while upgrading our home movie theater in our living room. I wanted to hide all electrical and video/audio wires. I did some research on how to do this correctly, while keeping a tight vapor barrier. Here is how I did it, step by step.

This is a section of the original wall where there is also a window. I started by removing the winow trim and cutting away 10 cm of our wooden floor to give room for the new wall.

With all the dry wall removed you can see the old 0.15 mm thick plastic vapor barrier. It should be placed on the warm side of the wall. In Norway that is the inside of the wall. It is, however, ok to have a maximum of 1/4 of the wall insulation on the inside of the vapor barrier.

Since the original insulation was in the vertical direction, I added the next 5 cm in the horisontal direction. Then I added the new vapor barrier which was taped together with the old one. Any holes found was fixed with some duct tape. I also useed silicon around adjacent walls. It is very satisfaying to have a completely tight barrier.

Here is where you see the advantage of having the inner most 5cm of insualtion inside of the vapor barrier. All electrical wires, can be hidden here without any worries of punctuate the barrier and getting condensing problems in the wall. The inner most 5 cm insulation was in the vertical direction.

Insulation on the inside completed, a full 20 cm in total for the wall. Some of the dry wall in place. To the very left you can see a hole for a speaker cable.

There it is. The completed wall with the first layer of paint.

You can find more technical details on vapor barriers here: Vapor Barrier explained

How I converted a car to an electric vehicle

2010-12-07T22:44:00.001+01:00

This brings back good memories from 1997 when I was the first in Norway to convert a car to an EV.

I spent about 200 hours on this conversion, and it was not really that hard. I got my parts from http://www.evamerica.com/ and made a deal with my wife to work in the garage every Monday after work. My old website from Geocities have some interesting pictures, particular on the clutchless design of connecting the original transmission to the electric motor. If your are thinking of making a conversion I would suggest you to check this out: How I converted a car to electric . It also have my log of the joy of driving an electric.

How much should tires be over-inflated to save gas?

2010-09-16T17:29:00.000+02:00

The sticker inside the door of my car suggest that tires should be inflated to 2.3 bar (33 PSI). I have usually been driving with 2.4 bar (35 PSI) in my tires. Before going on vacation this year, I increased the pressure to 2.6 bar (38 PSI). Since the car was loaded with my family and luggage this should be about right. It seemed to handle ok.

After the vacation I decided to leave the pressure at 2.6 bar to see if I could increase my mpg. I noticed that the car was not as comfortable to ride as usually, the ride was stiffer. When driving into a bend I noticed that as I turned the steering wheel more and more I would get to a point where the car would all of a sudden turn a bit more than what I was really turning the steering wheel. After a while I decided that it was just too uncomfortable to ride my car with over-inflated tires. When correcting my tire pressure I noticed a bit of damage on one tire. Then I looked closer, I found that the damage was all around the tire at the same distance from the shoulder of the tire. It was most on the outside shoulder of the front tire, but also on the inside shoulder. And also slightly on the rear wheel tires. I stopped by the local tire shop and the guy said that I must have hit something and that the dammage was small and nothing to worry about. I think the real reason is that the tires was so over-inflated that the dammage shows where the tire shoulder was when the tire was at 2.6 bar. I can picture the tire in a bend, and how the smaller area in contact with the road is strugling not to slip. Then it slips or skids a bit and the road tears loose a small part of the tire.

I was not driving enough to make any good data on what the gas savings might be from this, but based on the tire wear and umcomfortable ride, I can not recommend this. Check you tire pressure often. It is well documented elsewhere that too litle pressure increases the rolling resistance and hence also the gas used. So make sure you use the recommended pressure or just slightly above.

Summary in Norwegian: Sørg for å sjekke tryket i dekkene ofte slik at de aldri går under det som er anbefalt. Min erfaring er at +0.1 ekstra også går helt fint. Noe særlig utover det går for mye utover dekkslitasje og veigrepet.

Rebuild your car to run on LPG

2010-06-08T23:01:00.006+02:00

While waiting for the Citroen C-zero or the Nissan Leaf all electric vehicles, we rebuilt our Citroen Berlingo 2004 to LPG about three years ago. The cost of doing so was about US$ 3000 but in Norway gas cost about US$ 2 for a liter (about US$7 for a gallon). LPG cost less than US$1 for a liter. Our car is rated 7,4l/100km or 38,2 mpg combined driving cycle, which is equal to a CO2 of 175g/km. The good news about LPG is that it will result in a 15% drop in CO2, so our car is now a 152g/km. I wish more people would grab similar opportunities for saving both CO2 and money. It is really such a no brainer. Money wise we will break even later this year.

Summary in Norwegian: Hvorfor bygger ikke flere om sin bil til LPG? Det er overskudd på LPG gass, mesteparten bare brennes opp ute på oljeplatformen. Da er det bedre å brenne den opp gjennom motoren på din bil. Mange klimatiltak er direkte lønnsomme. Ombygging til LPG drift av din bil er et slikt tiltak. Driften har vært helt uproblematisk, selv uten årlige servicer på LPG anlegget. Der jeg fyller LPG gass opplyser de at LPG gassen i Norge er meget ren, og at det ikke er behov for årlig bytte av filter hvis man kjører lite. Bilde viser hvordan man kobler seg til LPG tanking i Norge.

Using PLX KIWI MPG to reduse fuel consumption

2010-03-02T18:29:00.015+01:00

I bought a KIWI MPG trip calculator to be able to measure the fuel consumption in my Citroen Berlingo 2004. My hope was that it would help me learn how to drive the most fuel efficient, and I will give it credit for teaching me a few things. It does, however, have some bugs. Here is my short test and review.

It all started out after reading the tips on Ecomodder.com. Reading, understanding and then following these tips will most likely have the biggest impact on saving you fuel. But I like statistics and to compete with myself using the least fuel. That is why I bought the KIWI MPG.

I plugged the unit into the OBDII port in my car. The KIWI MPG indicated that my car had a "CALP" sensor, which is the one that needs to be calibrated. After some days of driving, I changed the 1.00 value to 0.27 to get fuel consumption close to actual use. Then I have tested it for several months.

It is interesting to see the fuel consumption when driving. Sometimes a try to push the clutch pedal to the floor and just coast, and then compare it to having the enging engaged and running. But can the display be trusted? When going downhill with the gear engaged and no throttle, I have been told that the car should be using no fuel. The KIWI MPG should be showing 0, but it is showing something like 2.4 (liter/100km). Another bug is that the unit does not always start when starting the car. Perhaps as often as 1 out of 3 times it does not start. Then I have to use the on/off switch. When I stop the car, the KIWI MPG does not always stop. It thinks the car is running and the average fuel consumption keeps rising, which ruins the average function. Twice it has gotten some kind of hick-up, showing much too low fuel consumption. Turning it on-off-on brings it back.

The best I can say is that it is an educational toy. After all it is fun, and I have managed to lower my fuel consumption with 5-10% after using it, or is it just because I am using the techniques from ecomodder.com ?

Update: This winter I was not using my car for a week, and after that I could not start it. Flat battery. Then I recalled how I had noticed one morning that the entire windscreen had been covered by a thin layer of ice, except for one small spot. This spot was about a foot above the location of the KIWI MPG. You can feel that the unit is warm even when it is in standby. I have now disconnected the unit, and have had no problems starting the car later this freezing cold winter in Norway. So make sure you unplug this unit if you are not going to use your car for a week or so.

Summary in Norwegian: Har din bil ikke en forbruksmåler? KIWI MPG er en bensinmåler du kan ettermontere i de fleste biler. Imidlertid er jeg noe usikker på hvor godt den egentlig måler forbruket. Det er en morsom dings. Kan kappe kjøre med meg selv til jobben for å se om jeg kan forbedre forbruket fra dagen før. Men jeg er ganske sikker på at det er teknikkene fra ecomodder.com som er det som virkelig monner. Enheten bruker mye strøm i standby, så den bør frakobles hvis du parkere bilen over lenger tid.

DIY heat exchanger for your shower

2009-11-30T22:00:00.018+01:00

Update December 2011: You may now buy the new affordable DWHR unit for stand alone shower cabinets at the HeatSnagger Shop
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Update April 2011: Arthur and I have joined forces and are now working on a commercial, low cost DWHR unit based on this blog post. You may follow our progress at Meander Heat Recovery
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Nov 2009:
I got an E-mail from Arthur Kimmels. He has come up with a DIY concept for a small shower heat exchanger, a drain water heat recovery (DWHR) unit. I really like the simplicity of this design. His mail speaks well for itself, so here it is:

Hei Svein,

With interest I read your blog about miljødusj http://urge4lessenergy.blogspot.com/2008_11_01_archive.html. I had been walking around with a similar idea of building a heat exchanger for the shower (before I read about miljodusj, but inspired by some products on the Dutch market), and after some months of thinking and building I installed it today. Attached you will find some pictures of the unit. It is built of wood, coated with fiber glass and polyester. It measures 85x32x12cm. The water channels have an inclination of approximately 1cm/m. The heat exchanger is built of ca. 4m copper, 12mm diameter and soldered together. It works as 'counterflow'. A disadvantage of this setup is the pressure drop/flow reduction due to the long PEX/copper/PEX length (ca. 8m), but I measured this to be within acceptable limits for my setup. The measured temperature increase at a flowrate of ca. 10liter/min was 23.3(out) -8.8 (in) or 14.5degC. Total material cost was ca. NOK 1500, including PEX tubes to and from the unit. (The thermometer in the picture measures at the in and outlet, I removed the 'indoor' sensor from the housing and soldered it to some wire.)

Feel free to add to your 'blog'.

Kind regards, Arthur Kimmels

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Summary in Norwegian: Arthur har laget en enkel varmeveksler for dusj. Avløpsvannet fra dusjen brukes til å forvarme kaldtvannet som kommer inn i dusjen. Temperatur økningen på kaldtvannet er målt til 14.5 C. Det medfører at man bruker mindre varmtvann og dermed sparer energi. Spillvarme gjenvinning i praksis.

The most efficient way to boil water

2009-11-23T22:22:00.009+01:00

This is a follow up of a great article by Pablo at the Treehugger http://www.treehugger.com/files/2009/11/electric-kettle-stove-or-microwave.php where he tested the efficiency of different ways of boiling water. By bringing 350ml of 17°C water to a boil and measuring the energi used, he found the efficiency of using a pot on the stove to be 30.5%, a microwave 47%, and an electric kettle 81%.

I have been thinking of how to make coffee in the morning. I can use the drip brewer or the Frensh press pot. So I first repetead the Pablo test with our 2000W electric kettle. It took 77 seconds to bring the water the 83 C° up to a boil. Actually slightly shorter, but I timed it to the point where the kettle turned it self off. The specific heat of water is 4.180 kJ/kgK, which means that it takes 4,180 kWs to heat one liter one C°. Needed energy transfered to the water is then 0.350 l * 83C°*4.180 kWs which is 121.4kWs. The kettle averaged 2000 W and used 77 seconds, which is 154 kWs. From this I get the efficiency of my electric kettle to be 78%, which is close to what Pable got. Then I tried the drip brewer. It averaged 950 W and after 153 seconds it was done, but the next 15 minutes it turned it self on again four times for 6 seonds each time. So at the time of automatic shut off it had been running for 177 seconds. 168.2 kWs turns out to be an efficiency of 72%. I did this test with 350 ml so it could compare to Pablos test.
For us, a more realistic water use is typical 700ml, so after waiting for an hour, I redid the tests with twice as much water. The result from this was that the drip brewer was 95% efficient and the electric kettle 88% efficient. So for our family, the drip brewer is the most efficient way boiling water for coffee.

Summary in Norwegian: Det kreves store mengder energi for å varme opp vann. Derfor er det lønnsomt å være bevisst på hvordan man varmer opp vann. Konklusjonen fra denne testen er at en kaffe trakter er den minst energikrevende måten å lage kaffe på.

Moving hot air from ceiling to floor

2009-10-18T21:15:00.007+02:00

I have been contacted by a lady, Kari, that has a vertical pipe that she uses during the winter to move hot air from underneith the ceiling to the floor in her small house. It is about 8 ft tall, 4 inch wide and has a 7W fan inside the pipe. In her first year in the house she was often cold on her feet, but after installing the vertical air transporter her feet were much warmer. Before starting the fan in the morning she measured 18C (64F) three feet off the floor, and 13C (55F) at the floor. After running the vertical air transporter for 3-4 minutes the heat was distrubeted more evenly such that the temperature at the floor also was 18C (64F). She claims to have saved a lot on her heating bill by using this for one winter, comparing it to the heating bill from the previous winter. She has been trying to get Enova interested in the consept and get them to promote the consept as a general energy saver in Norway, but without much luck. So is this a working consept for saving energy?

I think it can be compared to using a celing fan. During the summer it blows cold air down at you and you feel cooler because of the wind chill factor. During the winter it can be reversed to slowly rotatet the air up and then down the sides of the walls. It must be done slowly so it does not create any noticeable wind chill factor, as it will make the air feel cooler. Slowly mixing the air evenly is known to save energy during the heating season. Energy Star: Using the Ceiling Fan Year Round It should not matter how you mix the air as long as it is done slowly. Kari measured as much as 5 C difference between floor and 3 feet up. I would think that in particulare a house with cold floor will benefit from mixing the air, as this will probably be where the highest difference is in vertical temperature. If mixing the air will help you lower the average temperature in the room with 5 C then the saving would be as if you turned down your thermosate with 5 C, which should give a noticeable difference on your heating bill.

Great savings with extra water heater insulation

2009-08-31T22:03:00.013+02:00

We have under the kitchen bench a 120 liter / 2000W electric water heater from http://www.oso.no/ Several spots outside this was warm to the touch, as indicated on the picture. I called technical support at Oso and they could confirm that it was OK to add extra insulation anywhere, also including the plastic lid that cover the ectrical wiring inside. So I used some spare insulation material and wrapped some plastice aound it all, and taped it up. For the pipes I got special insulation to wrap around the pipes. I have previously measured the standby energi consumption to be 1,8kWh/day. With the added insulation it as dropped to 1,2kWh/day. (You can measure the standby losses by measuring the energy used for a weekend when you are not at home using hot water. Use a plug in meter and just read off how many kWh that has been used to keep the water hot when you where gone).

We have the heater set at 65 C. Our family of five use about 7-8kWh a day for heating water.

I noticed how the power cord to the heater got warm when it was on. I cut off 1,2m of it for an additonal saving og about 4W ( 2,4m wire, 1mm2 copper, and about 8A) when in use :-)

Summary in Norwegian: Kjenn på utsiden av din varmtvannstank. Er den varm kan du med enkle midler spare mye energi. Bruk det du måtte ha av isolasjonsmateriale (Glava e.l.) og pakke det inn i plast til slutt. Alle varmtvannsrør bør også isoleres. Besparelsen hos oss var 0,6kWh/dag. Du kan også spare noe ved å forkorte tilførsledningen til et minimum.

Cleaning and checking the heat pump

2009-08-30T21:13:00.020+02:00

We got an offer from Lier Everk to get a service agreement for our Panasonic CS-CE7GK air-to-air heat pump. For NOK 1200,- (about $200) they would come and clean our heat pump every 2nd year. I did some research and it looks like you easy can do this yourself.

The first part is to clean the coils of the unit. Turn off the power of the unit. Remove the filter. Vacuum any dust that can be seen. Use luke varm water and dishwasher liquid (Zalo) and just spray your indoor coils. Use a towel to collect excess water dripping from the unit. The outdoor unit is cleaned the same way. Spray on. Wait for a while for the dish washer liquid to disolve dirt. Then use a garden hose with low pressure and apply water in the opposit direction of the normal airflow. Be careful not to bend any coil fins. Let the unit sit for some hours to dry before turning on power.

The second part is to check that it still delivers the heat (or cold) that it should. According to the Pabasonic service manual the difference should be at least 14 C in heat mode and at least 8 C in cooling mode. I checked ours by setting the temp to 27 C. Inlet temp showed 23C and outlet 42C. A difference of 19C (The unit using 484W). Then for fun I set the additional "Powerful" mode. Inlet temp is then 23 C and out take 48 C. (The unit using 985W). A differance of 25 C. Outdoor temperature was 13 C. If the temperature difference is less than 14C you should check that all coils are clean. If cleaning does not help, it is time to call for service.

Summary in Norwegian:

Du kan enkelt rengjøre din varmepumpe selv. Vask ved å spraye på med lunkent Zalo-vann. Utdelen kan i tillegg spyles med hageslange med lavt trykk, aluminiums finnene må ikke bøyes. Det skal være en temperatur forskjell på minst 14 grader mellom luft som går inn i inndelen og luft som kommer ut av den ved normal drift.

Insulate your unused chimney

2009-08-30T20:10:00.022+02:00

Some years ago we had a fireplace, but we never used it that often, and there was always a cold draft from it when it was not in use. So we sold the fireplace (and got space for a home movie theater instead..) and sealed off the chimney. Much of the draft was gone, but last winter I noticed that the chimney was still very cold when touching it. Both on the ground floor, but even more on the first floor. No wonder when all that cold outside air fills the entire chimney.
So in preperation for this winter I made a simple unused chimney insulation. I used a total of seven plastic bags, each filled with some insulation material. After tieing the top of each plasticbag, I connected them all together with a string. Using a long stick a pushed the first one about 4 m ( 12 ft) down the chimney.

Then I pushed the next one a little bit shorter, and the next even shorter, and so on until the last one finshed it off right at the top of the chimney. This should defenitely slow down any cold air trying to go down the chimney this winter. Should we decide to get a fireplace in the future I can easy pull all the insulation bags out of the chimney using the string that interconnect them all.

Summary in Norwegian: En ubrukt pipe er en kald pipe. Du kan isolere pipa ved å trykke plastposer med isolasjon ned i pipa. Hvis du forbinder dem alle med et tau, så går det greit å få dem opp igjen hvis du skal bruke pipa igjen.

Dryer balls save no energy

2009-03-04T21:34:00.028+01:00

I stopped by Elkjøp in Sandvika and met this sign on my way to the cash register.

"Save energy, 25%, save money". This caught my interest, since I am always looking for ways to save energy. My first thought was that this is too good to be true. At the cash register I asked if they had some sort of proof that Dryer balls actually work, if not I would consider this being fraud. He told me to wait, and then left. After 10 minutes I had to go. I saw several customers buying Dryer balls at kr 199,- ($ 28) while waiting. Walking home I got really mad, and decided to get to the bottom of this. The day after I was back and bought my set of Dryer balls. The next morning I put it to the test.

In my test I used our normal family load of some towels, pants, T-shirts, underwear and socks. After washing and spin drying it, I used a digital scale to record the exact weight of the clothes. Then I threw them all in the dryer and set it on "cupboard dry". When the dryer stopped I measured the weight again. The difference is exactly the water removed, or how much drier the clothes are. The other part was to find the energy used. A plug in energy meter ( http://www.clasohlson.no/ 36-2897 ) on the power cord of the dryer makes this task very easy. So I recorded the kWh used, and also room temperature, humidity, and the time for the dryer to finish. This I did first with no Dryer balls and then with Dryer balls. And then I repeated all this one more time for a total of 4 runs.

By dividing the energy used by the liter of water removed from the clothes, we get a number that can easy be compared. My four runs show results between 1.29 and 1.35 kWh needed to remove one liter of water. The average for the use of Dryer balls was 1.31 kWh/l and without was 1.32kWh/l. This is less than 1% difference, and a very clear conclusion that DRYER BALLS SAVE NO ENERGY.

On the http://www.dryerballs.com/ they say that : "The 25% saving in electricity every time you use the dryerballs® in your drying machine is another terrific reason why dryerballs® is a winner for you and the environment, saving you money and substantially reducing energy consumption." The company backs this with a test report: "dryerballs® have been scientifically tested to ISO standards at an independent, fabric care laboratory". Robin Green at http://www.green-energy-efficient-homes.com/dryer-balls-review.html have managed to get hold of what is supposed to be this test report. You can read his review of it. In my opinion, it clearly indicates that there has never been any case with a possible 25% energy saving.

I have also tried to contact Dryer balls on all three info E-mail address I have found. The E-mails all get back with a "recipient failed permanently" message.

I give to you all the details in the tests I have performed. You will find the full recording of my test data here:

http://www.itec.no/svein/dryertest.pdf

You can verify how the data was collected by looking at my video documentation of run 2 and run 3:

http://video.google.com/videoplay?docid=7711913355735063353
http://video.google.com/videoplay?docid=3689334162010114221

In March 2009 I will spend some time publishing my testresults, and contacting companies still selling Dryer balls. This product needs to be taken off the shelves!

I will visit Elkjøp again. They have a 30 day money back warranty, so I know I will get my money back. The challenge will be to have them remove it from the shelves.

Whereever you have bought your Dryer balls, take them back. Refer to this blog and ask for a full refund. If they do not give you a refund, go shop somewhere else.

In April the Norwegian Consumer TV Report program "FBI" got interested in dryer balls and made this TV program based on my test (Norwegian): http://www1.nrk.no/nett-tv/indeks/166310

and this article (also in Norwegian) http://www.nrk.no/programmer/tv/fbi/1.6548305 The conclusion was that Elkjøp now is giving everyone a full refund with or without a receipt. But they are still selling the product...

Summary in Norwegian:

Mars 2009: Elkjøp i Sandvika selger Dryer balls som jeg har testet meget nøye. De sparer overhode ikke noe strøm. Har du kjøpt noen så bør du gå tilbake og kreve kjøpe hevet basert på villedende reklame. Henvis til denne bloggen. Firmaet Enklere liv selger nå også " Tørkeballer - sparer deg og miljøet ". Etter det jeg kan se av bildet i deres helsides annonser i Budstkka og Aftenposten, så er dette samme produkt som Elkjøp selger.

April 2009: NRK Forbrukerinspektørene blir interessert i saken og sender "Tørkeballer fungerer ikke!" Se på nett-tv http://www1.nrk.no/nett-tv/indeks/166310 eller les artikkelen på http://www.nrk.no/programmer/tv/fbi/1.6548305 . Lefdal og Elkjøp selger ikke lengre tørkeballer på nettet. Mange andre aktører har imidlertid kastet seg inn i et forsøk på å tjene noen penger. Ikke rart, når man kan kjøpe dryer balls i Kina for $0,66 (ved kjøp av 1000 stk + frakt) så man kan jo si at marginene gode. Imidlertid ser det ut til at salget går tregt, da prisene stuper. I utlandet får du nå nesten kastet dryer balls etter deg.

August 2009: Elkjøp selger igjen tørkeballer på nettet. De skryter fortsatt av opptil 25% energi besparelse. Andre steder har dempet ned dette med energi besparelse, og selger de mest som erstatning til tøymyknere. Det er helt klart markedskreftene som regjerer. Sløve konsumenter som ikke gidder klage på produkter som ikke virker gjør at Elkjøp kan profitere videre på tørkeballer.

Juni 2010: Det er ikke til å tro. I en liten slagskurv i hvitvare avdelingen selger de fortsatt trøkeballer. Innpakningen på dem så litt slitt ut. Mon tro om det er her de selger videre tørkeballer som kunder har returnert?

Reduced water flow

2009-03-01T14:07:00.013+01:00

When you reduce the flow of hot water you also reduce your use of energy. In our house we have two levels of water flow reduction. First our house is connected to the municipal water through a pressure limiting valve. It was probably originally put in because this areas may have too much water pressure, which can cause household appliances to malfunction. Safe pressure is usually less than 10 bar (145 PSI). We have turned this down to 2 bar (29 PSI).

In addition to this we have added faucet aerators on all outlets, except for the one at the bath tub. The faucet aerator introduces air into the flow of water coming out of the faucet. That makes it seem like more water is coming out, but it's actually using less water. I have installed two different types ( http://www.clasohlson.no/ vannmengdebegrenser 30-9848 and 30-9849). The claim was that they will reduce the water flow with 40%. I have measured before and after the installation, and the reduction was almost exactly 40%. So whenever someone is washing their hands, less warm water will flow, and there will be a reduction in energy needed for heating water. Our kids often drink cold water straight from the faucet, which is not quite as comfortable to do with all the air introduced, so this is a slight drawback. They complained the first day, but did then get used to it.

Here is an article from EPA about water flow reduction:

http://www.maroochy.qld.gov.au/sparkandgypsy/documents/fact7_flow_red.pdf

Draft in a keyhole

2009-01-21T23:04:00.010+01:00

One night going to the bathroom I noticed a small but cold draft. I was passing the doors the our children's bedrooms. They sleep with their windows open at night and this was a windy night. So I could feel this draft, but their door to the hall was closed. This puzzled me, but as I got closer to the door, I realized that the draft was coming out of the key hole! I used a piece of tape to stop the draft. It is almost invisible to the eye, and does help. It is common knowledge that any drafts must be stopped. No point in adding much new insulation to your house if the cold wind is blowing through it any how. In our living room I have also insulated the keyhole. Here I have used a bit of black electrical tape on the inside of the hole, and also a bit of insulation material behind that. This door separates our home movie theater from the rest of the house. So here the motivation was originally to sound proof the door, but it works for draft proofing as well.

Summary in Norwegian: På natten sover vi med åpne vinduer og dørene stengt til resten av huset. En vinter natt på vei til toaletet merker jeg at det kom iskaldt trekk i gangen. Det kom fra nøkkelhullet! En tape fixet problemet. Dette understreker hvor viktig det er at man finner kilder til trekk i huset og så tetter dem. Det kan like gjerne være en skjev dør eller dårlig tetting rundt vinduer som lager trekk.

Insulate the trapdoor

2009-01-04T16:21:00.007+01:00

Perhaps even more important than insulating the trapdoor is to make sure there are no drafts in between the ceiling and the trapdoor. Moist hot air finding the way into the attic during the winter season will condense. This will be a threat to wood beams and roof wall boards as they might rot. I have used a P-profile seal strip (http://www.clasohlson.no/Product/Category.aspx?id=251254#34-237) to make sure the trapdoor is properly sealed when closed.

Then I removed the ladder. For insulation I had some leftover Litex insulation that is self supporting and can be glued together. On top of this I added a 6mm plywood sheet before screwing the ladder back on top of this. I would think that the insulation now is at least twice as good as before, by judging the thickness of the insulation.

Insulate the attic

2009-01-04T16:07:00.009+01:00

Insulating the attic is one of the best way to improve insulation with little effort, I have heard. The cost of getting insulation is limited and there are no structural changes that is needed. In theory it is just a matter of spreading out more insulation. I started out in one corner of the attic and moved around all the stuff we have up there as I added 7 cm sheets of insulation. I added as much as possible while still allowing air to circulate above the insulation. It was a lot of work. If I where to do it again, I would empty the attic completely, and then pay a company to come and blast insulation all over the place. A lot more easy, and probably slightly better when it comes to cover everything without any leaking cracks.

Summary in Norwegian: Jeg har etterisolert loftet. Skulle jeg gjøre det på nytt så ville jeg ha bestilt noen til å blåse ut isolasjon, for å krype rundt på et trangt loft var svært anstrengende. Men det ble veldig bra til slutt.

Add a new dimension to your Christmas light decoration

2008-12-12T21:30:00.033+01:00

Over the years we have improved our Christmas decoration outside our house. Adding fun while cutting the need for energy.

It all started out many years ago with four chains of lights, each with twenty light bulbs. All our neighbours had nice decorations with white light bulbs, while ours where multicolored party lights. We put them in our only tree, a plum tree at our entrance. Neighbors where joking that they needed sunglasses to look at it. Next year I added a motion detector (http://www.clasohlson.no/ 36-1084). When people or cars pass by, the plum tree really lights up with its 80 x 5W of light bulbs. It gets even more attention than before. The motion detector has a built in timer and a light sensor. The timer is set to make the light go on for only 20 seconds, while the light sensor make sure the light goes on only when it is dark. This cut the daily energy use from a shocking 24h x 80 x 5W= 9.6kWh to an estimate of 0.5h x 80 x 5W=0.2kWh.

The year after when my wife was going to through away an old speaker, I got the next idea for the plum tree. Music! Christmas music! Together with the kids we compiled a CD with a mixture of traditional and crazy Christmas songs. This we put in an old CD Walkman, set on REPEAT ALL. This connects to an old amplifier that I bought used. Then comes the little trick with the speakers. Between the speaker and the amplifier there is a on/off switch controlled by the same outlet that turns on the plume tree light (a relay controlled by 230VAC, such as 36-1984 from Clas Ohlson, http://www.clasohlson.no/Product/Product.aspx?id=35483378). So when movement is detected the light comes on and the speaker is connected to the amplifier. Sparkling colors and Christmas music for 20 seconds or as long as there is movement outside our house. One year we had a mother and a small child visiting every day. The little boy wanted to hear the music and see the ligths. This reminded me that we should turn off the music at night when neighbor kids sleep with their windows slightly open, so I added a timer (32-3835 http://www.clasohlson.no/Product/Product.aspx?id=20823096 ) to the power line of the amplifier. The timer is set to be off between 11pm and 7 am. For a while I was worried that some people might dislike these lights, but I do believe they appreciate the fun and the surprise. Two days ago we had three teenage girls laughing loud outside. Walking back and forth a couple of times in some crazy disbelief of the musical-plume-Christmas-party-light-tree. This evening I left my cell phone video recoder on next to the tree for a while, and caught this comment from someone running by:

Perhaps you can adopt some of these ideas? If you already have some outdoor Christmas lights, please do go and get a timer to turn the lights off when most people are asleep and during the day time. Easy savings. Next time you add an outdoor outlet, have one made that is connected to a motion detector. Use it for your Christmas lighting, and perhaps you can come up with a fun use for Halloween too?

6.Can the washer machine benefit from the Miljødusj?

2008-11-24T22:12:00.005+01:00

The Miljødusj is designed to heat the incoming cold water based on the drain water leaving the shower at the same time. It must be simultaneous to work efficient. I was first thinking of hooking up the washing machine together with the shower, but I was told it would not do much good. The washing machine does not drain anything until it is done with the washing cycle, and then the next water that flows inn would be for rinsing, which I believe is usually just cold water. But then I thought, what if I connect just the water inlet to the washing machine from the preheated outlet of the Miljødusj heat exchanger, and forget about the drain water going through it. Then I could start the washing machine right after my shower and harvest the left over energy. (Or possibly run it at the same time as I shower?) After my morning shower, I set the shower mixer to just cold water, and emptied 2 liter at the time while measuring the temperature. It gave be this table, that shows the energy value of the "leftovers" when I am done showering. I am not sure how much water our washing machine needs, but I would say it should be less than 8 liters. If so, it should be possible to squeeze out 85 Wh by also connecting the washer machine to the Miljødusj. Many ifs, and not a big potential saving. Based on this I decided not to connect our washer machine, at least not for now.

5.Mesuring the cold water temperature increase of Miljødusj

2008-11-19T22:35:00.013+01:00

I used two digital thermometers to measure the in and out temperatures of the heat exchanger under the shower cabinet. Each thermometer was strapped with a rubber band to where the pressurized water is connected to the Miljødusj, one on connection 1 which is incoming cold water, and the other on connection 2 which is the preheated water going to the shower.

My initial test setup was performed by cooling it all down first. I let the cold water flow in the shower for 5 minutes, then I took a quick shower. The plot clearly shows how the temperature of the out pipe to the shower increases from 15 to 26 °C (59-80°F) . The lowest graph shows the temperature increase which is about 11 °C . (The increase after the 6 minute mark is after I stopped showering).

The day after I measured my own shower which is usually fast, followed by our oldest son, Simen, who takes longer showers. ( Yes, teenager..) Looking at the graph you can see that the temperature in the room, and then also of the initial water in the heat exchanger, is 22 °C. When I start to shower the red curve shows the temperature of the preheated cold water pipe going to the shower. It is increasing all the way along as we shower. The blue curve shows the temperature of the incoming cold water pipe. Looking at the second shower you can see that it bottoms out at 14 °C . After a shower it heats up due to the last drain water passing through the Miljødusj and also later from the room temperature. The lower curve is just the difference between the two upper ones, showing the temperature increase, which is really what we are looking for. The difference show 11 °C . But is this the real temperature increase of the water? No, it is the temperature increase measured on the outside of the connecting pipes. If you recall the pictures of the inside of the Miljødusj, the out pipe goes from the back of the box and above the drain water back to the pipe connection to the shower. I assume the pipe temperature here is close to the water temperature inside the pipe. Around 25 °C . The incoming cold water is out of the picture I managed to take, but it is most likely very close to all the parallel pipes and in contact with the drain water. To check for this I just measured the cold water coming out of the tap. It showed 11°C . So when I measure 14 °C outside the pipe, the inside water is really just 11 °C. I am confident that the real cold water temperature increase in our shower is close to 14 °C (57 °F) from 11 °C to 25 °C.
Continue reading here: 6.Can the washer machine benefit from the Miljødusj?

4.Conecting the small heat exchanger

2008-11-17T22:23:00.015+01:00

It seemed to be simple to connect the Miljødusj to the shower, but it turned out to be a bit of a struggle. Removing the lower skirt of the cabinet and pushing it into place was the easy part.

Prior to buying the unit I had measured the height clearance to be almost 10cm ( 4 ") so I knew the heat exchanger would fit. If the space had not been there I could have bought some rubber stand offs to increase the clearance underneath the shower cabinet.

I bought the cheapest flexible water pipes I could find (http://www.clasohlson.no/) which felt more rigid than flexible. Fighting with them underneath the shower cabinet I realized that the 3/4" connection did not fit. As can be seen on the picture, the center metal piece of the connection has a slightly larger diameter than the inner hole diameter of the no 2 connection on the Miljødusj. I had to buy a small 3/4-3/4" nipple pipe to fix this problem. Installing it with 20 rounds of sealing tape made it leak prof (1o rounds was not enough). They might have increased the size of the inner diameter on newer versions of the Miljødusj. Make sure to check this, or buy the flexible pipes they sell with the product.

This next picture shows the installed heat exchanger underneath the shower cabinet. The closest pipe is the drain water from the shower entering the heat exchanger. The pipe behind is the, now somewhat cooler, drain water exiting away and down the house drain. It turned out that it is important to have these pipes at a continuous incline to ease the drain water flow. Originally one of them was twisted upwards to the bottom of the cabinet, and it made the drain water flow too slowly out of the cabinet. If your shower uses a lot of water pr minute, it will be a good idea to make the drain pipes as short as possible. Using solid drain pipes, instead of the flexible ones in the pictures, will increase flow as they are smooth on the inside. On the cold water connections in the back of the picture you can see some red rubber bands. These I used to strap my temperature sensors to the pipes to get the facts on the temperature gain of the incoming cold water.
Continue reading here: 5.Mesuring the cold water temperature increase of Miljødusj

3.Looking inside the heat exchanger

2008-11-16T16:54:00.007+01:00

The first I did after receiving the Miljødusj or small heat exchanger for the shower, was to try to figure out how it was put together. Using my cell phone I manage to take some pictures showing the inside.
The cold water is entering in the left corner that we can not see in the picture, but the water can flow in the copper connection all the way up to the black arrow. From this connection there are 10 parallel copper pipes making the cold water (blue arrow) flow to the right. On the right side there is a similar pipe connection that extends all the way in to the bottom wall of the box. From this connection there is another set of ten pipes making the water flowing back to the second half of the first connection (yellow arrow). At the top of the picture you see the exit pipe (darker yellow) feeding the preheated cold water to the shower.

So there are a total of 20 pipes that looks like they have been pressed half flat and then soldered together to form one big copper area. The drain water from the shower will flow over this area.

The drain water from the shower enters the heat exchanger at the end of the big pipe on the right. I put a flash light in it so it can be more easily seen. The warm drain water will counter flow with the cold water coming in, which is the best way to do a heat exchange. The copper area is tilted 2 cm (about an inch) to make the drain water flow slowly over it all and exiting out the hole from where the picture has been taken. Since the cold water flows in parallel pipes, then there should be no problems with pressure drop in the cold water supply.

The next step was to connect it to the shower. Continue reading here: 4.Conecting the small heat exchanger

2.The small bathroom heat exchanger - miljødusj

2008-11-15T20:00:00.009+01:00

I thought I should give Norwegian websites a try in my urge for finding a small heat exchanger for our shower. To my surprise, a new product had just been introduced to the Norwegian market by http://www.miljodusj.no/ (Norwegian only). (It should also be available in Austria, Slovakia and Germany. More information on the product can be found at the SUP technology site in the Czech Republic http://www.sakal-ovt.cz/eng/shower.htm ). There it was. Just what I had been looking for. I talked to the salesperson who explained a bit more how it worked. Cold water from the house pipe connects to 1. Drainwater from the shower flows into 4 and heats the copperpipes of coldwater inside the box, before it exits out and down the drain at 3. Preheated cold water will exit from 2 and on to cold water pipe of the shower. The salesperson said the coldwater would increase 12-15 C (53-59F). He claimed it to be actual measured numbers.

I ordered it and prepered to put it to the test.

Continue reading here: 3.Looking inside the heat exchanger

1.Looking for a heat recovery unit for our shower

2008-11-03T22:56:00.011+01:00

I have found several good systems for heat recovery of drain water from a shower, that I can not use.

They all work on the same basic idea of a big water pipe with one or many smaller pipes wrapped around it. The drain water from the shower heats the big copper pipe, which in turn heats the smaller pipes where the incoming cold water to the shower flows. There is a heat transfer from the drain water to the incoming cold water. When the cold water heats up, we can use less hot water and still achieve a nice warm shower as before.

Here are some links to different units of the vertical type:

http://www.saskenergy.com/saving_energy/drainwaterheatrecovery.asp
http://www.enviroharvest.ca/heat_recovery.htm
http://www.retherm.com/HowItWorks.htm

The problem is that all of them have this vertical design and can not be fitted underneath our shower cabinet that is placed on the floor. They are great if you are doing work on your house, or for installation when you build your house. We have a shower cabinet that is fully enclosed and abut 4 inches above the floor. I need to fit a heat recovery in this tight space. I was thinking that I could just get a long 32mm hose and the fit an equally long 12mm copper pipes inside of it, forming a simple heat recovery system. I even went to the library to borrow some books on thermodynamics to learn more. Then a month ago I was so happy to find someone selling a heat recovery unit that will fit underneath a shower cabinet. I decided to buy one.

Continue reading here: 2.The small bathroom heat exchanger - miljødusj