Energy Saving in Oman - Part 2

By Akira Katayanagi

It seems that the summer has arrived in Tokyo. Last time I introduced the energy saving project in Oman, but this time I’d like to get away from engineering and look at culture and education in Oman.
Firstly, the state religion in Oman is Islam, so there are mosques throughout the city. When you mention the Arab world the mosque is a popular image, and in Oman many people pray 5 times a day (before sunrise, noon, afternoon, right after sunset and before retiring). For this reason, offices, shopping centres and hotels generally have a prayer room. Even though it tends to make meetings and presentations a little long, they are often stopped for prayers.
Islam is seen as a rather strict religion by most Japanese. Drinking alcohol is not allowed under Islam and women generally cover their figures in a long black dress called the “abaya”. Oman is girded by the Arabian bay, the Straits of Hormuz and the Gulf of Oman with many beautiful beaches but you will not see Arab women relaxing in their swimsuits there. There aren’t so many men on the beaches either do they are very quiet.



Sohar beach

However, there are differences in the severity of restrictions depending on area. Oman is considerably more liberal than neighbouring Saudi-Arabia, with many working women and it is accepted that women drive.

Next I’ll talk about language and education. Arabic is the official language of Oman but English is widely spoken. Traffic signs, notices and signboards are basically displayed in Arabic and English so there are no difficulties getting around. Then over half of Omanis can speak English fluently. This is mainly due to the fact that there are a lot of foreign workers in Oman, so it’s necessary as a means of communication. The population is made up of about 2,000,000 Omanis and 700,000 foreign workers.
Another reason why English is fluent is education.

The course of study in Oman is similar to that of Japan, however, the policy at universities is very different. Classes and all teaching materials are in English with none of the textbooks translated into Arabic. It is said that English is hardly studied until an Omani enters a university. I heard that Omanis hardly study English until an entering university but work on it intensively in the first year. Basic subjects and majors are learned from the second, but as these are studied completely in English, it is acquired out of necessity.

On hearing this I suspect that many Japanese, like myself would think “what an effective education system! We should do likewise.” However, if you ask Omanis their opinion, the think that technical subjects should be studied in your mother tongue and that we are lucky to be able to do so. They have to use English to learn technical subjects and this is more difficult than you might imagine. It is only studied superficially as a second language, It is very hard to master subjects in depth and as a result, the level of technical expertise in engineering seems to be underdeveloped. I’m not saying that this opinion is 100% right, but it is thanks to this project that I was led to weigh these ideas.

A mosque in the city of Muscat

Akira Katayanagi,
International Projects Group

http://www.ptmtokyo.co.jp/

Energy saving in Oman – Part 1

Energy saving in Oman – Part 1
For 3 weeks from the middle of May I visited Oman to investigate energy saving conditions and power consumption in residential units, as part of a project to draft energy saving measures there. It exactly coincided with the holding in Japan of the world cup qualifying match between Oman and Japan.

I covered this project in and earlier blog, but with the aim of promoting the saving energy policy to control electric power consumption in Oman which an electric power demand is rapidly on the increase, this project team is composed of specialists in various fields in order to formulate the most appropriate energy saving policy for Oman through a succession of meetings with the government of Oman.

I really got to experience the climate and temperature in Oman. From the standpoint of energy usage the year in Oman can be divided into 2 main periods, the summer season from April to September, and the rest of the year when basically little or no power is necessary for either cooling or heating. In particular the heat peaks between June and August, when the average temperature reaches 40ºC. It was my first experience of such heat, and just walking in the mid-day left me dizzy. Then on the roof top where the A/C outside units were installed it exceeded 50ºC, and sweated profusely while working there. However, the mid-day humidity was low at about 20%, so it was not so bad in the shade. With this kind of heat, I suppose that the cooling of offices and shopping centres to below 22ºC is looked on as a kind of complimentary service.

What was of deeper interest on this trip were the power measurements actually taken in households, and what temperature settings or specifically the temperatures at which people live, in order to understand current power usage. Over 50% of power generated in Oman is used by households so the first thing to do is to promote residential energy saving. Next time I’ll introduce the actual measurements we took.



Thermometer in Muscat displaying a reading of 41ºC

An office





Akira Katayanagi – International Projects Group
http://www.ptmtokyo.co.jp/ 

















Visualization of CFD calculation results using 3D PDF

I work in the Environmental Group and mainly work on CFD computer simulations. Today I’m going to introduce the 3D PDF tool which can be used to demonstrate the results of CDF calculations.
CFD is the use of computers for fluid analysis, and we use it for prediction and evaluation of indoor air current distribution and the wind environment of the city. Specialised visualization software is used as a way of confirming the results of CFD calculations and to draw up distribution maps for temperature and wind velocity, however, to present the results to a third party a jpeg image is printed out and attached to a report. However, even though the CFD calculation is carried out in 3 dimensions, this information is finally presented to the client in the form of a 2 dimensional representation.

The 3D PDF resolves this issue. PDF is an electronic document format developed by Adobe Systems and there is a 3D version of this software. A example can be downloaded from the location below.

A visualisation of CFD calculation results using 3D PDF: the thermal environment of the human body:
Wind speed distribution: http://www.ptmtokyo.co.jp/blog/humanEnvironment_U2.pdf
Temperature distribution: http://www.ptmtokyo.co.jp/blog/humanEnvironment_T.pdf

The files should open in Adobe Reader to display images representing the air flows and temperature distribution around the human body.

3D PDF is different form usual electronic documents; as with CAD documents as the image can be rotated and we can zoom in an out using the mouse. A lot can be displayed in 3D PDF with the commonly used Adobe Reader. The advantage is that this format can be used to present the results of CFD calculations to a third party as a three-dimensional form without the need for specialised visualization software. This is extremely useful when explaining the results of CFD calculations to clients.

Shinya Ogata, Environmental Group
http://www.ptmtokyo.co.jp/

The ideal air conditioned environment

Today I’m writing about ‘the ideal air conditioned environment’.

This theme was inspired by my travel experiences in Spain, when I travelled around staying in Madrid, Toledo, Granada and Barcelona, and visited cathedrals in each city.

Entering cathedrals I usually noticed how cold it was. Outside short sleeves were enough, but in the cathedral it felt cold even with a coat on. Of course an air conditioner would not be effective. That’s down to the large heat capacity. The heat capacity of 500kcal/m3 K is based on the stone from which cathedrals a mainly constructed of, about twice that of timber or plaster board. In other words, stone is 2 times more difficult to heat up. Additionally, I think the walls are about 1m thick so the heat capacity is really beyond comparison to typical Japanese buildings.

I wondered whether these cathedrals were the “ideal air conditioned space”. It seems a little strange to talk of an air conditioned space with no air conditioners but what I really mean is a temperature controlled space without air-conditioning. Of course the climate of Spain and the small number of openings or windows has an impact, however, the “coldness” which gives the Cathedral its air of solemnity is dependent on this heat capacity.

I also visited the Sagrada Família which is also in Spain, but inside I didn’t experience the same atmosphere as within the other cathedrals. I didn’t feel the same kind of “coldness”. The reason, I think, being the number of openings in the building and the number of people inside. Without the cold atmosphere, there is still an overwhelming feeling of solemnity, which is perhaps one of the reasons why the Sagrada Família attracts attention from all over the world.Without the usual coldness found in other cathedrals, perhaps the Sagrada Família was, for Gaudi, an ideal air conditioned space in which he was aiming at harmonisation with nature.

Energy saving project in Oman

In February I spent 2 weeks in Oman, working on plans for energy saving.With the recent rapid economic growth and increased development, there has been a big growth in power demand and the goal of this project, awarded to JICA (the Japan International Cooperation Agency) was to draft energy saving policy, and promote energy saving including improvements in efficiency on the power demand side and by limiting energy consumption.

Oman is situated on the south-east of the Arabian Peninsula in the Middle-East, with the United Arab Emirates to the north-west, Saudi-Arabia to the west, and Yemen to the south-west. The Straits of Hormuz which has been the scene of international tensions is within Oman’s territorial waters. The country has an area of 310,000km2, of which 80% is desert.　The total population is about 3,000,000 of which about 1/3 are foreign residents. Incidentally, Japan with an area of 378,000km2 has a total population of 128,000,000. Oman has a desert climate with summer temperatures reaching 40 degrees in summer. The religion is Islam and Thursdays and Fridays are holidays – Friday is the Islamic day of rest, equivalent to the Christian Sabbath.

Main industries are oil and natural gas, from which most of the government revenue comes from. Nevertheless, as with other Arabian countries, petroleum output is declining and it is said that crude oil and natural gas reserves shall be exhausted in 20 and 40 years respectively. The stated goal is to eliminate the states dependency on oil.

I stayed in Oman for 2 weeks, gathering information from government and power companies, investigating buildings and building services equipment, as well as the electrical appliances available there. Oman is an economically prosperous country with high levels of safety and civic order, and looking at the electrical appliances there showed they were not so different from what is available in Japan.

There is still the feeling that the diffusion and implementation of energy saving has yet to be realised, but this can partly be blamed on the availability of cheap electricity. For example, household energy charges range from 2 to 6JPY per kWh which is very cheap (in Japan the charges range from 17 to 24JPY per kWh). What made a big impression on me was that this is a country where the air-conditioners never stop running during the 6 month summer period. In fact, looking at the power consumption for a single household, 3000kWh ~ 5000kWhiwas consumed during a single summer month. That’s 10 times that of the average household in Japan which uses about 500kWh in one month.

On an office rooftop

Office building substation
The substation is the property of the power company

I will be visiting Oman again in May and August, to accurately measure power consumption and get a good grasp of the conditions there to put together appropriate energy saving policy. I look forward to being able to put together successful proposals using the superior equipment and systems and to help Oman’s energy saving efforts.

Akira Katayanagi

Illumination Standards

Hello this is Kaoru Maeyama.
This post is about standards relating to brightness.

As part of our energy saving measures after the earthquake in March, I think that our efforts at switching off unnecessary lights were a little patchy. Since we started to try and save energy in July last year, we removed some of the tubes from the ceiling fixtures, and we’ve got by with lighting at about half the usual levels. It does seem dark and a few people are occasionally turning on their own desk lights to compensate, but in the main everyone got used to it.
So, while we really want to save energy we are not too happy at being stuck in the dark, and people likely hesitated to complain as they don’t really like to. But, how do we decide the necessary levels of brightness in the first place?

1．Several standards
Brightness is indicated using an index of luminance in Lux (lx) units. Here in Japan the most commonly used standards are the domestic JIS standards, and in general office spaces the standard lighting level is 750lx.　In addition to this, under Japan’s Industrial Health and Safety Law, lighting levels of over 300lx are necessary in offices where precision work is carried out. However, looking overseas the standard range in the United States is from 200 to 300lx. Compared to this the JIS standards levels are very high at 750lx.

2. Reviewing the JIS standards
JIS lighting standards were finally, after a period of 30 years revised in 2010. Until then the standard for offices was given as a range of between 500 and 1000lx however, an easily understandable representative value of 750lx was usually specified.
However with the recent power shortages, the range of 500 to 1000lx was restored under the JIS lighting standards in May 2011. Under this review, appropriate lighting levels were set depending on the actual conditions, with the intention of promoting energy conservation. I would venture to say that this reflects the opinion that the levels specified under the 2010 revisions were excessive. There is a tendency in the design of new buildings to increase lighting levels in competition with other buildings and also above the JIS standards. A situation which is not conducive to energy saving.

3．Future brightness levels
When lighting designs are implemented, there are seldom complaints that it is too bright, but there are bound to be complaints if it is too dark. There are not a few lighting designers who will install excessive lighting in order to avoid dark spots. There are likely facility managers who have the same tendency when planning new offices.
　Incidentally, we managed to cut our ceiling lighting from 800 to about 400lx however, by using desk lights occasionally there were hardly any complaints. Actually, we have been working on detailed drawings in a 400lx lighting environment however, personally I felt it was no hindrance at all.

Desktop luminance 389lx

I think those who are concerned with lighting environments may feel a further study is necessary to ensure there is no excess or insufficiency in lighting levels. So rather than disabling light fixtures, we need to reduce the number of fixtures installed from the very beginning.
Recently, this proposal is being accepted here and there, and seeing this makes me really feel that things are changing.

Kaoru Maeyama, Environmental Grouphttp://www.ptmtokyo.co.jp/

Results of summer time energy saving - part 2

This is Hokuto Nakamura from the Environmental group.
Following on from Shuji Imura, I’m going to evaluate the energy saving measures we took over the summer, based on the data.

Areas covered
1) Real time monitoring
2) Air-conditioner tuning
3) Lighting/office equipment

1) Real time monitoring



Monitoring panel

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

We set up a monitoring panel to help with the implementation and evaluation of our energy saving ideas.

 

 Peak power consumption
The importance of understanding peak power this summer was commonly acknowledged in Japan however, when the peak occurs is not so clear as electricity is invisible. Based on experience our engineers were able to make a reasonable guess however, it is difficult to judge accurately to within two hours. This time we were able, by real time monitoring of power usage, to take action such as switching off lights before peak power usage was reached.
Our peak power usage this summer occurred at 11:30am on August 12th at 38.3kW (35% lower than the previous year). This shows the results of the effort put into saving energy this summer, and while it is not a result of the monitoring, it puts a numerical value on the power saving activities carried out and there is a connection to the improved awareness of energy saving.

*Assumed values based on meter reading and outdoor temperature changes.

 Energy saving activities utilising monitoringNext, we opened windows to successfully monitor the outside air temperature and humidity (only for a couple of days). On July 21st 2011, a large typhoon hit Tokyo and the surrounding region. On the days before and after (21st, 22nd) it was obvious that the outdoor air temperature was rapidly dropping, so we shut down as many of the air conditioners as possible and tried to cool the office by opening the windows. The indoor temperature tended to be higher than on the 20th when the cooling system was operated as usual however, there was a 25% reduction in electric power usually required for one day’s cooling. It is difficult to forecast, but it was possible this time with the monitoring system we set up. This will be especially useful in April and may when the temperature is not so high.

Period of fresh air cooling in 2011

 

2) Air-conditioner tuning

Imura-san (who wrote the previous blog post) led efforts to review all air conditioner remote controller settings. There were two main improvements.
   (1) Setting the weekly timer to switch off at 19:00, with the option to turn them back on.
   (2) Based on a review of temperature settings and temperature sensors which were 27°C it was decided to put them at 28°C.

I’m not going to go into all the details here, but here is a month by month comparison of last year’s metering data and data gathered this year.

Comparison or air conditioning power

 

Compared to 2010, we achieved an energy saving of about 34% for air conditioning. This value came as quite a surprise to our engineers and gave serious pause for thought about our previous lack of consideration. The results of monitoring showed that about 2% of cooling came from fresh air, shutting down the air conditioners at 19:00 accounted for a reduction in power consumption of about 10%, and the review of temperature settings gave us a 22% reduction. If fresh air cooling is about 2% and shutting down the air conditioning gives a power reduction of 10%, then the change in temperature setting gives a reduction of about 22%. It is easy to get complacent about controlling air conditioner settings, so everyone needs to consider it carefully.

3) Lighting /office equipment power

Lighting
 One way of saving on lighting power was to reduce the number of lighting fixtures in use. However, you need to be careful how you do this or you might well end up using more power. Our approach was that if you didn’t miss one of the light units when turned off, then it was deemed a waste of energy and disabled. By using illuminometers and asking staff how they felt about the light levels, we were able to select which units to disable and determine the best arrangement. Maeyama-san will go into the details in another post.
About 100 fluorescent lighting tubes were removed (about half ), so using the following rough calculation:

 40　[W]   ×   100　[units]   =　4,000 [W]   →　4.0[kW]

 The above calculation gives us a saving of about 4.0kW. Prior to disabling some light units, lighting power was about 9.0kW, which is an energy saving of about 45%.

 Office equipment power  Reducing the brightness of desktop displays is one good way of saving power with office equipment. The graph below shows our results. Normally it is possible to save about 10W by reducing the brightness from the display default. This also has a beneficial impact on air conditioning power consumption as less heat is given off. However, it shouldn’t be reduced to the extent that it causes eye strain.

The following calculation shows the power saving for 40 people in the office

10　[W]  ×  40　[persons]   =　400 [W]  or  0.4[kW]

 On top of this saving of around 0.4kW we made a real effort to switch off monitors when not in use. Compared to 2010, we achieved a 32% reduction in power consumption. The savings were from 25% lighting and 7% office equipment.

Conclusions In comparison with last summer, this year we achieved energy savings of 34% (over a period of 2 months). The figure below shows a breakdown of power saving, and it is clear that lighting (38%) and air-conditioning adjustments (33%) make up a large portion of savings.

Breakdown of power reductions

 As a result of our efforts we achieved a reduction of 35%, and the amount of power saving between August and September was 34%, so while this is commendable, I think our previous power usage calls for serious reflection. We need to look further into ideas (such as heat stored in the building structure etc.) that we didn’t put into practice this time, and we also need to think about energy saving during the winter. I’d be happy to hear from anyone who would like to put these energy saving ideas to the test.