■ Initiatives to obtain the first "NearlyZEB" certification in public buildings in Tokyo

Shinagawa City Environmental Learning Exchange Facility Ecol Toshi (hereinafter referred to as this facility) is a person who practices environmental education and communication on a daily basis in the Shinagawa City Environmental Basic Plan formulated in March 2018. The aim is to realize an environmental city that connects to the times, and to develop it as a facility where you can experience and learn about the environment.

In the “Basic Energy Plan” (decided by the Cabinet in April 2014) and the “Global Warming Countermeasures Plan” (decided by the Cabinet in May 2016), the government has significantly reduced energy conservation without reducing environmental quality inside and outside the room. The spread and realization of ZEB, which leads to, was indicated as one of the goals.

In response to this, in the development of this facility, at the beginning of the basic plan, which began to be considered in FY2018, the realization of ZEB, the first ward-owned facility, was stated. In the examination process, with the aim of ensuring the realization of ZEB, the order for design consignment will be determined by a "proposal method" that requires a technical proposal from a design office that has acquired ZEB certification. After a public offering and a meeting for selection in April of the same year, a design contractor was decided in July of the same year.

In the design work implemented from FY2019, we have been studying from the initial stage to further improve energy-saving performance, such as 1 outer skin function 2 plane shape 3 zoning. In addition, the four systems and equipment used in this facility have been designed to realize ZEB by combining those in the world, taking into account the ease of future equipment renewal.

This facility is located in a corner of Togoshi Park, and the plan is to reduce the height of the building as much as possible by greening the walls, putting harmony with the rich greenery of the park first. In addition, this tile, plaster wall, etc. are used as building materials to ensure continuity with the Yakuin Gate located on the east side of this facility. Wood was heavily used for the interior and exterior, and in that case, from the viewpoint of local governments that interact with Shinagawa Ward and local production for local consumption, those from the Tama area, which has forests in Tokyo, were adopted. In order to properly manage forests, a series of cycles of "growing, cutting, using, and planting" are effective in preventing global warming, and these enlightenment will be implemented at this facility.

①Outer skin performance In the WEB program (* 1) used for ZEB judgment, the BPI (* 2) value was 0.47 (design PAL * / standard PAL *) (* 3), which was planned to have higher skin performance than ordinary buildings.
The glass used in the opening surface is We are working to reduce heat loss by using low-E double glass.
The outer walls other than the openings were lightweight concrete (ALC) and sprayed urethane (50 mm).
At the same time, although it does not directly contribute to energy saving calculations, the wall surface is greened from the north side to the east side of the third floor to block direct sunlight, and the effect of reducing the temperature rise of the wall surface due to the transpiration effect of greening is expected. ②Plan Among the short-form buildings with the same floor area and the same height, the square floor plan with the smallest outer wall area is used to reduce the outer wall area that receives external heat load.
Many of the openings in the living room are on the park side (south side), and the eaves are 3m deep based on the solar height and sun direction of the summer solstice. By installing, the heat load of the living room due to direct light is greatly reduced. Regarding the hot summer west day, even if there is this deep eaves, it is expected that direct light will enter the room, so it will be blocked with a louver eaves provided 1.95m from the opening floor.
At the same time, taking into account the outstanding wind direction in the area, ventilation windows using atriums and stairs will be provided to allow air to flow at the temperature difference in the building. Natural ventilation We expect that the non-air conditioning period will be set as much as possible to reduce the air conditioning load during operation. ③zoning On the part facing the outer wall with high heat load, a backyard such as a flow line space, a warehouse, a machine room, etc., and a toilet that is a non-air conditioning space are arranged to enclose the living room area such as an exhibition room and become an air conditioning space. This has led to a reduction in the heat load in the living room. ④Systems and equipment 1. Heat Source Equipment In addition to the high-efficiency air-cooled heat pump tiler, the heat source equipment uses a geothermal heat pump tiler because the site has abundant groundwater.
First, the high-efficiency air-cooled heat pump chiller adopted a high-COP (* 4) type that enhances cooling efficiency by sprinkling water on equipment to reduce primary energy.
Next, in the geothermal heat pump tiler, a boahole type, which is a closed circuit, was adopted, and the pump lifting process for geothermal exchange was reduced to save energy. At the design stage, a geothermal heat exchange test was conducted in advance, and the required number of underground heat exchangers (100m deep) (6 units) was determined.
The temperature and humidity set for each room was 28 degrees in summer, 50% relative humidity, 19 degrees in winter, and 40% relative humidity, and the heat source capacity was selected. 2. Air conditioning and ventilation equipment The air-conditioning system uses radiation air conditioning, air conditioners, and fancoil unit.
Radiation air conditioning is air conditioning and heating by heat exchange with the human body directly without air, and is said to have the effect of reducing transport power and making it difficult to generate uneven room temperature. In the community lounge on the first floor, the entrance hall, and each exhibition area on the third floor, this radiation air conditioning is used, and floor air conditioning using the central air conditioning system is also used. By using these air conditioning systems, "living area air conditioning" that intensively airs the area near the floor where people are active is performed, thereby minimizing the air conditioning space and reducing the air conditioning load. The central air-conditioning system uses a subtropical thermal separation type air conditioner, and plans to ensure comfort even when the room temperature is reduced by controlling the humidity. In addition, a method is used to control the amount of blowout wind using a variable quantification device for each air conditioning zone. At the same time, the primary energy volume was reduced by optimizing the amount of outside air introduced by CO2 control. The first-floor office, where the room usage time is irregular, the second-floor rooms, and the third-floor multipurpose room are air-conditioned individually. 3. Use of rainwater To use rainwater, a 40m3 rainwater storage tank is installed in the underground pit, and a pressurized water supply pump is used to clean toilet water.
This pump is incorporated into the storage battery system for the purpose of continuing to use the toilet in the event of a power outage.
4. lighting equipment All lighting equipment uses LED lighting, and some uses human sensors and illuminance sensors to control energy consumption.
The sensors are installed in toilets, warehouses, machine rooms, etc., and are used to ensure that lights are turned off when unused.
The illuminance sensor is installed in rooms where natural lighting can be expected, such as the community lounge on the first floor and the multipurpose room on the third floor.
5. Hot water supply facilities Since the hot water supply facilities have limited locations such as water heaters and nursing rooms at this facility, individual hot water supply systems have been used, and hot water storage electric water heaters have been installed at each location.
In the calculation of ZEB, there are environmentally friendly hot water supply facilities, but this facility was adopted due to the effects of hot water supply usage at this facility.
6. Elevating facilities The elevator was equipped with an 11-seat machineless elevator. Although there are functions that lead to more energy savings, such as speed control devices and regenerative power storage systems, the facility has been rejected because it is a low-rise building.
7. Photovoltaic power generation facilities The photovoltaic power generation facilities will be installed on the roof of this facility, and the number of panels installed will be 288 (93.6 kW), and the amount of power generation per day will be about 215 kWh.
The power generated will be charged to storage batteries and used in buildings.
In the event of a power outage, it must be used together with a storage battery to supply lighting and a part of the outlet of the community lounge on the first floor and the multipurpose room on the third floor, as well as toilets and offices on the first floor. The minimum necessary supply to the required room is to be provided.
The installation angle of the solar panel will be tilted three times mainly to the south side, and the installation area of the panel will be secured as much as possible. 8. Power storage equipment On the roof of this facility, A 120kWh storage battery was installed. In the event of a power outage, use it together with solar power generation equipment to supply lighting and outlets in the community lounge on the first floor and the multipurpose room on the third floor, and to continue even in the event of a power outage, such as toilets and offices on the first floor. The minimum necessary supply to rooms that need to be used is provided. In the event of a power outage, it is assumed that power supply will be continued for about 72 hours using a storage battery + solar power generation. 9. BEMS A BEMS (* 5) will be installed in the office on the first floor to understand the energy usage. The collection data obtained from BEMS is tabulated by sector, such as air conditioning, ventilation, hot water supply, and lighting. From these data, adjustments will be made to lead to optimal operation when operating equipment. ■ Primary energy consumption forecast The primary energy consumption design value using the WEB program is 0.41 for BEI (* 6) and 0.09 for BEI including solar power generation equipment, excluding solar power generation equipment for the entire building. Acquired.
The breakdown of primary energy consumption per unit area of each facility is as follows. (Unit: MJ/m2/year)
・Air conditioning equipment
Design value: 474.34 reference value: 1,218.17（0.39）
・Ventilation facilities
Design value: 46.06 reference value: 98.17（0.47）
・lighting equipment
Design value: 73.91 reference value: 242.94（0.30）
・Hot water supply facilities
Design value: 47.71 reference value: 20.67（2.31）
・elevator
Design value: 14.09 Standard value: 14.09（1.0）
・Photovoltaic power generation facilities (energy utilization efficiency improvement facilities): 523.50 ※1 Web Program: Energy consumption calculation program for buildings.
By entering the area of the building, the area and use of each room, etc. in this program, the standard energy consumption of the building is calculated.
Next, by entering information such as equipment specifications, the size of each room, and the type of insulation, the design energy consumption of the building is calculated.
For example, if (design energy consumption) ÷ (base energy consumption) is 0.25 or more and 0.5 or less, ZEB Ready is achieved. ※2 BPI: Criteria for annual heat load calculated based on external skin standards ※3 PAL*: Annual heat load per floor area of the interior space of the building ※4 COP: A value that indicates the cooling and heating capacity per 1kW of power consumption of cooling equipment, etc.
The larger the value, the better the energy consumption efficiency. ※５ BEMS: Building Energy Management System
Building Management System to Optimize Indoor Environment and Energy Performance ※６ BEL: The ratio of primary energy consumption of design buildings based on the Energy Consumption Performance Calculation Program (WEB Program) when compared with standard buildings. Except for renewable energy, when BEI ▲ 0.50, it is judged that ZEB has been achieved.
As a result, the reduction and control method of the heat source equipment capacity of the air conditioning equipment, the setting illuminance and illuminance control of the lighting equipment, and the solar power generation equipment (energy use efficiency equipment) have greatly contributed to the improvement of the BEI value.