The heating load of the low-carbon standard is 5.7 times more lenient than the German Passive House standard.

The heating load of the low-carbon standard is 5.7 times more lenient than the German Passive House standard.
Actually, it's not a good thing, but in this month's issue of New Housing "+1"
I would like to publish an article I wrote. It took me quite a while to write it.
We compare the energy conservation standards of Japan, Germany, and Switzerland under the same conditions.
I have never seen any other literature that does this, so I hope you will find it useful.
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To give you the conclusion first, in the case of areas such as Tokyo and Osaka, if we compare them on the same level,
Even the low-carbon standard was found to be 5.7 times more lenient than the German Passive House standard.
Also, the commonly held belief that "heating the whole building consumes a lot of energy" is no longer true today.
In low-carbon buildings, "heating only when people are present" is more common than passive house standards.
Heating the entire house uses only 1/2 to 1/3 of the heating energy.
The standards will become mandatory for all new buildings in 2015.
This introduction is quite long, but the text is the same as in the article below.
During 2013, we will build houses equivalent to the German Passivhaus standard (private standard) and the Swiss Minergie
The completion of these two houses has brought a lot of attention from various quarters.
I was asked to introduce these in a lecture.
Unless people understand the system and how it works, they won't be able to understand its meaning.
First, for details on the Passive House standard, see Miwa Mori's "Building a good house according to global standards."
The German private standard is currently considered the best in the world.
In Germany, all new buildings, both buildings and homes, must meet the Passive House standard.
It is expected to become mandatory, but as of now it accounts for 10% of new construction.
In contrast, the Swiss Minergie standard is also a private standard. Germany's Passive House
The standard focuses on the ultra-high performance of the outer skin, while the Minergie standard focuses on the outer skin performance.
Although it will be slightly lower than the current rate, we will try to use solar heat and biomass as much as possible as the energy source for hot water and heating.
The main focus was on reducing the overall primary energy required for these by using mass.
These are extremely strict standards. Currently, 25% of new buildings and 10% of recovery buildings in Switzerland are Minergies.
It is said to meet the standards. In addition, the performance of the envelope is on par with the passive house standard.
The Minergy P standard has been improved, and Minergy does not use many drugs.
There is even a standard called P Eco, and this house falls under this standard.
People who have heard of the Passive House standard may ask, "Isn't it 120 kWh/mXNUMX/year or less?"
I think many people understand it as, "Isn't it less than 15 kWh/mXNUMX per year?"
The 120 mentioned here is the standard value for primary energy consumption per square meter per year, 1.
This refers to the standard value of heating load per square meter per year.
The energy regulation is 120. In Japan, it is called heating load.
The criteria are not clearly stated.
Just explaining what primary energy is would take up too much space, so I'll go into more detail here.
I will leave that out, but gas and kerosene are the amounts used in the home, and electricity is the amount used in the home.
I thought it was the amount of energy from coal, oil, and gas that power plants use to make the
I think it will be easy to understand if you just say this. In this case, when electricity comes to your home,
This value is called primary energy.
This is called the power conversion factor (PEF), but it varies depending on the power generation situation in each country.
In order to compare the circumstances, it is necessary to understand the PEF of each country, otherwise the comparison cannot be made on the same level.
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In addition, in Japan, primary energy is used for "heating" and "cooling."
This includes "ventilation," "hot water supply," "lighting," and "home appliances and cooking."
Passive House Standards
Among "home appliances and cooking equipment," washing machines, refrigerators, and other appliances that are essential for daily life are called
This only includes "Leopalace Home Appliances". In the Swiss Minergie standard
It only includes three items: heating, ventilation, and hot water. You need to include these items to compare.
That's why we actually compared these items.
The only items common to Japan, Germany, and Switzerland are "heating," "ventilation," and "hot water."
However, when it comes to hot water, Japan is the only country that has the custom of taking a bath.
In addition, the use of solar hot water heaters is common in Germany and Switzerland.
If we include "heating" in the comparison, it will be completely meaningless.
The yellow part shows a comparison of the PEF when ventilation (with heat exchange) is performed and converted to the same value as in Japan.
The figures are as follows (Table 1).

Looking at it this way, the Passive House standard and the Minergie P standard are almost equivalent.
On the other hand, in Japan, even homes that meet the top runner standards are 2.64 times lower in low-carbon housing.
The standard is 3.44 times as lenient as the revised energy conservation standard (equivalent to the previous next generation), which is 3.88 times as lenient.
We can see that the Japanese standards are mandatory standards, passive house standards and Minergies.
The standards are private standards, so it is unfair to compare them on an equal footing, but there is a big difference.

By the way, in most European and American countries, the standards that the government sets as obligations are called "minimum standards."
The only thing the government can "mandate" is something similar to the minimum wage.
It is a "minimum standard" and no country would make a higher "ideal standard" mandatory.
It seems very difficult. Therefore, every country has its own national standards as "minimum standards".
There are "private standards" that are the ideal standard. Japan has "next-generation energy conservation standards"
Because of the bad name, few people have the perception that this is the "minimum standard."
It seems that the number of buildings has decreased. It is clear from the structural field that the number of buildings with earthquake resistance grade 1
This is the limit of the standard, and the ideal level, Class 1.5, is XNUMX times the earthquake resistance.
I think it's exactly the same diagram.
By the way, in addition to the six regions, we also compared the standards for all regions in Japan.
In this calculation, the Japanese standards are determined based on the recommended specifications of each region.
In other words, it is based on the assumption that the colder the region, the higher the insulation specifications.
This is a standard figure. In Germany and Switzerland, regardless of the temperature of the location, primary energy
The heating load is set uniformly.
The insulation in this region can be relatively thin, while the cold regions of the north require extremely thick insulation.
In Japan, the further north you go the more you need to drink.
You may know that the specifications are becoming stricter. However,
Even if the specifications are met, the north requires a lot more energy to maintain the same indoor environment.
We can see that this is the standard for consumption.
There is another puzzling aspect of Japanese standards. That is partial intermittent heating and cooling.
The standards are stricter if the entire building is heated and cooled, while the standards are more relaxed if the entire building is heated and cooled.
To use an example of a car, "People who drive light vehicles must achieve 20km/L or more,
People who drive a Crown have a large car, so if it gets 10km/L or more, that's fine.
This can only be interpreted in the same way. In fact, this system is being abused to secure subsidies for zero-energy projects.
At the time, many businesses received subsidies by deliberately cooling and heating the entire building, which meant lax standards.
I was there.
Next, how much of the "heating load" required by Japanese standards will be calculated from the primary energy used for heating?
We calculated backwards to see what they were thinking. (Table 2)
Germany and Switzerland are burdened from the start
Since there are standards for heating loads, we used them as they are.
"Total amount of heat required to keep the room temperature constant over the heating period
It may be easier to understand if you think of it as "a result of adding heat to the room".
It is determined by "airtightness" and "solar radiation acquisition", so what kind of heating equipment should I use? What is the PEF value?
It has nothing to do with whether the heating and cooling load is sufficient or not.
Let's compare them.

What we can see from this is that when we look at the heating load alone, the difference is even greater than when comparing primary energy.
Even with the envelope performance of the top runner standard, it is below the passive house standard.
This is four times worse than the previous standard. The revised energy conservation standard is six times worse than the previous standard.
This means that it takes four or six times as much energy to maintain the same temperature.
This is nothing other than that. In fact, many Japanese home builders also display heating loads.
Even when looking at the "Building Energy Saving Health Map," most major manufacturers have heating loads
It can be seen that it is within 80 to 95 kWh/mXNUMX.
http://tatemono-nenpi.com/map/
We also compared the heating and cooling loads in areas other than the six regions (Table 6).

Looking at this, there is a 16-fold difference in one area of Hokkaido.
It is thought to be colder than the coldest area in Germany, which is why I think the values are like this.
For example, the average January temperature in Asahikawa is -7.5°C, while in Hamburg, in the far north of Germany, it is XNUMX°C.
That's about it. Since the amount of sunlight is different, it's not an equal comparison, but 1.5 degrees is
This corresponds to Fukushima. Since Fukushima is one of the four regions, we compared areas with similar outdoor temperatures in January.
Even so, we can see that there is a difference of 11 times.
Here is another system that the majority of practitioners and clients are thinking about.
We also compared the standard values for "partial intermittent heating and cooling."
Looking at this, we can see something surprising. In warmer climates, partial intermittent heating does indeed save energy.
The amount is clearly smaller. However, the difference is much smaller in colder regions.
This may be one of the reasons why whole-house heating has become the norm in cold regions.
However, it is important to note that even with partial intermittent heating,
This is well above the standards set by Germany and Switzerland for whole-house heating. What this means is
"Even if Japanese people endure the cold and sacrifice their health, in Germany and other countries, the whole building is warm and cozy.
It uses more energy than a Swiss home.
The natural temperature difference (room temperature without heating) assumed by the energy conservation standard (next-generation energy conservation level) is at most
7℃. Even in Tokyo and Osaka, the temperature will be around 1℃ in the early morning on the coldest day in January.
This means that on days like this, the room temperature is likely to be below 10°C in the morning.
What I want to say here is not that "Japan's standards are therefore bad."
Germany and Switzerland have declared that "20 degrees Celsius is a temperature that must be maintained at all costs in order for people to stay healthy and comfortable."
However, it is absolutely necessary to reduce CO2 emissions. Energy prices are definitely on the rise.
If we work backwards from our goal to meet these conflicting conditions, the only way is to minimize the heating load.”
I believe.
It is inevitable that the mandatory standards will be tightened. However, we, the construction industry,
Of course, we have a great responsibility for the "health" and "comfort" of each customer, but we also have a great responsibility for the building.
As long as it exists, it will have a significant impact on "CO2 emissions" and "energy imports."
It is said that the average primary energy emitted by a single house is 75GJ, while that emitted by a single car is roughly 22GJ.
Moreover, the average lifespan of a car is 11 years, so cars are replaced frequently, and the fuel consumption is reduced every time a car is replaced.
We will continue to do our best to provide the best possible service to our clients, not just to their health and comfort.
It is necessary to be aware of this and design that the number of units will affect a large amount of energy consumption.
Germany has already decided on a target percentage for reducing energy consumption in all sectors and by when.
Working backwards from there, it is determined what percentage each area must reduce at this point.
I think that business goals can be decided in this way, but even if they are decided in this way, they will be carried out exactly as planned.
It is well known that the chances of reaching your goal are low.
However, the current standards in Japan are based on the current standards of building materials, construction, and the industry.
It is decided based on requests from organizations.
I think it's going to be very important to have a responsible attitude.
Of course, energy saving means low running costs.
By building homes like the ones we have introduced, most people can live warm and healthy with very low utility bills.
Even if you are a frugal person who does not use heating at all, it is important to make sure that the minimum room temperature does not fall below 15°C.
In summary, designers should ensure that people with any lifestyle can enjoy a minimum level of health and comfort.
You will be able to.
That's all, but if you have any thoughts after reading it, please let me know!