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The Building-Energy Manager's Association of Japan
(Source: Managing Energy-Saving Technology in the Building)

This association has been conducting an energy-saving diagnosis project as an aid project of the former Ministry of International Trade and Industry since the fiscal 1996.
This diagnosis service is a free project, which is conducted taking two days in principle. Two professionals, partner-up, selected from member companies of this association, are sent to the client's office.

Diagnosis items are listed below:
1. Analysis evaluation of real energy consumption in the building
2. Energy-saving diagnosis and measure planning on the building and the facility
3. Report of an improvement proposal
Below is a flow chart that shows a process of energy-saving diagnosis.

Figure. Energy-Saving Diagnosis Flow

In addition, this association set up the "Committee of Creating a Guideline of Energy-Saving Diagnosis," as an entrusted project by the Ministry of International Trade and Industry in the fiscal 1998 in order to stereotype diagnosis measures, and made a report with professionals' participation from related industries.

1. Calculation of Energy Consumption Rate
Heat value of fuels is used for energy except electricity and the value including generating efficiency and transmission loss is used for electricity. Then, they are converted into primary energy in order to eliminate the apparent difference depending on energy source used.

* Points to Keep in Mind

· Isn't regional air conditioning system being used? If it is, the heat source equipment and its efficiency at the heat supply center should be figured out.
· Isn't co-generation system being adopted?
· Aren't business hours unusual?
· Isn't there energy intensive equipment such as a large scale computer?
· Aren't there much turnover in the population? (Connection to an underground shopping center or a subway station, etc.)

2 .Comparison with a Database on Energy Consumption Rate
Calculated energy consumption rate and necessary energy consumption are compared.
Necessary energy consumption is gotten from the data of a building with the same usage, picked up from a range of statistical materials in "Investigation Report on Architectural Energy Consumption," issued by this association every year.

3. Method of Figuring out Monthly Energy Consumption Analysis and the Problems
Appearance of change can be seen from the situation of monthly energy consumption per each fuel based on energy consumption data.
By creating a monthly chart of energy consumption rate, air-conditioning energy consumption during cooling period and heating period can be figured out when between periods are bordered. The result of this data analysis can be a reference to confirm whether there is useless energy consumption such as cooling in summer or heating in winter or not.

* Points in Diagnosis

(1) When the mountain and the valley are clear:
· When quantities consumed are different between cooling/heating periods and middle periods: The mountain parts can be regarded as air-conditioning energy consumption.
· Size of air-conditioning energy consumption can be cleared at some level depending on whether convex parts are big or small.
· In an office building, a summer peak time is almost never higher than a winter peak time. In that case, there is a problem in air-conditioning heat source.
· When monthly quantity consumed is the lowest middle periods, which means April, May, October, or November, cooling and heating can be distinguished bordering that point: Operation of cooling in summer and heating in winter.

(2) When the mountain and the valley are not clear:
· When the lowest energy consumption is not middle periods: The building might be an all year cooling. Cooling and heating usage situation should be checked.

4. Appraised Diagnosis of Energy consumption for specific use
Although it is possible to use it when the consumption for air-conditioning is measured, which is seldom taken in general. Therefore, it is getting to be necessary to estimate the figure for specific use.

5. How to Calculate Energy Consumption Rate for specific use
(1) Primary energy of heat source

(2) Annual heat source load factor

(3) Energy consumption of pump and fan

(4) How to estimate energy consumption of conveyance system

6. Lighting Energy Consumption
· Calculating method of lighting energy consumption rate
∑(Lighting electric power × The number of the lighting set up × Annual Running Hours)=Annual lighting electrical power consumption → Convert into the primary energy consumption rate→[F]

7. Energy Balance Check (An example in case of an office)
Seek the percentage of the whole extended to energy consumption rate per each part after calculate the primary energy consumption rate per each part.
By checking these rates, it will be possible to specify the place, which might have a problem for using energy.
As points (in case of an office),

· Isn't energy consumption related to air conditioning more than the half of the whole?
→([A] + [D] + [E]) ÷ Energy Consumption Rate ≠ 0.5
· How is the balance between heat source and conveyance in air-conditioning energy? (Isn't the energy for conveyance more than that of heat source?)
→[A] > ([D] + [E])
· What is the rate between air conveyance and water conveyance?
→[D] : [E] = 1 : 2approximately
· Isn't lighting energy more than the fourth of the whole?
→[F] ÷ Energy Rate ≠ 0.25

As a point, common buildings and general usage are presumed in these evaluations, the amount of energy consumption and consumption patterns are different depending on specific usage or characteristics of the buildings. Therefore, it is necessary to figure out previously the actual situation of the buildings, facilities, and their usage, and put them in mind at evaluation.