Efficient use of energy simulation in the early design phase

Transcription

1 The higher offices are not sufficiently cooled the first level offices are correctly cooled 600 W/m2 at 11h00 SOUTH facade Architectural and climatic control systems choices Efficient use of energy simulation in the early design phase Pierre Jaboyedoff, Partner With contribution from Kira Cusak Sorane SA The design of high performance buildings require the use of modern simulation tools. Presentation of the use of different simulation tools in the process of designing high performance bioclimatic buildings. Simulations integrating buildings and systems are the only way to guarantee the expected results. Simulation tools allow studying the interaction between the environment and the building with the HVAC and other passive and hybrid systems? Example of applications of sophisticated tools during the integrated design process Paradox of high energy performance Energy efficient buildings and systems: The simpler and more bioclimatic the buildings are, the more complex the design process is More sophisticated design tools needed Systemic analysis Example: Radiant cooling, slab cooling Natural and hybrid ventilation systems Adiabatic cooling Earth tunnels Rock bed storage No wind Solar protections and natural ventilation The use of high performance solar protection systems combined with high inertia and natural ventilation allow to reduce significantly the cooling requirements even in some of the Indian climates 1

2 38m 60 postes de travail 1065 m2 SHON Plan libre Espace fermé Réunions Box individuel Reprographie Sanitaires Locaux techniques Ascenseur Interior blinds External movable blinds SHGC > 40% SHGC < 10% Movable blinds inside double facade elements Study of the optimal shape, facade HVAC systems, and SPV for a high rise building in Paris SHGC < 12% Option 1: Square deep floor plate (2000 m2), poor envelope, no dynamic solar shading device, mechanical ventilation without heat recovery (reference case for comparison with typical existing high rise building) 27m 2

3 Option 2: Square deep floor plate (2000 m2), good quality envelope, dynamic solar shading device (Solar gain coefficient = 15%), mechanical ventilation with heat recovery, natural ventilation on the peripheral zones (Compact high performance building) Option 3: shallow floor plate (2000 m2, 130 m width, 15.4 m depth), good quality envelope, dynamic solar shading device (Solar gain coefficient = 15%), mechanical ventilation with heat recovery, natural ventilation on the peripheral zones (Shallow plate bioclimatic design) 65m 36m 69 postes de travail 1189 m2 SHON 53m 13,83m 13m 19m 18m Plan libre Espace fermé Réunions Box individuel Reprographie Sanitaires Locaux techniques Ascenseur 25m 47m 11m 26m 15m 13m 15m 16,5m Option 4: shallow floor plate (2000 m2, 130 m width, 15.4 m depth), good quality envelope, dynamic solar shading device (Solar gain coefficient = 15%), mechanical ventilation with heat recovery, natural ventilation between peripheral and central zones (Shallow plate bioclimatic design with cross ventilation) 44m 3

4 TRNSYS parametric model developed specially for such studies (including HVAC, photovoltaic panels on the facade) Parametric generator for studies with a tool like TRNSYS Turn Equa-kJ_per_hr_to_kW Radiation Weather data Psychrometrics type_965_lighting Equa_light_summary Shading W Sky temp Ventil-Return HVAC333_1a Light Thresholds Shading N Shading E Lights Cooling Building Temperature Power Type65d-Front Equa-Generator Sumofheatcool 28b-OU1 28b-OU2 Equa-sommes Type55 Type55-2 Type65d-vent-Light 25c-OU4 25c-OU5 25c-OU7 25c-OU8 Schedules_lighting Development of specific tool allowing parametric studies by varying quickly parameters like: o Geometry of the building o Windows to wall ratio o Glazing and dynamic shading characteristics o Natural ventilation, mechanical ventilation, hybrid systems o HVAC system choices, heat recovery, o HVAC system performances o Passive and hybrid systems and combinations o Shading+Light Type94a_Front Type94a_Back Shading S Type94a_Left Type94a_Right Mec Vent Equa-Persons-PC Nat. vent. Equa-Control-VentNat Type22-Front Type22-Left Type22-Right Type22-Back Type22-Center Type2b Energy performance index of the 4 options Energy Performance index of an existing tower Measured Energy Balance (Final Energy: 2007) o EPI: 43 kwh/m2-yr OFS Tower, city of Neuchâtel kwh/m2-an Elec. Technical devices Elec. Lightning + PC s Elec. Heating+Ventilation Cold Heat Final Energy 2.5 4

5 Primary energy of the 4 options Net primary energy requirements Study of the optimal facade design for a high rise building Analysis of the wind distribution (direction, speed frequency) Analysis and comparison of the performance of different natural ventilation systems of openings including lamella movable blinds in the double facade elements by Computational Fluid Dynamics simulation 5

6 CFD modelling of the façade system with offices Movable lamella blinds between double glazing inside and single glazing outside Automatically controlled natural ventilation openings Option 1: Openings through slot (initial architectural proposition) Option 2: openings through horizontal rain protection screens (optimised solution) 6

7 Option 2: openings through horizontal rain protection screens (optimised solution) Option 1: Openings through slot (initial architectural proposition) Volumes where the temperatures is above 26 C are filled with orange color Example of a study on how to efficiently reduce cooling needs in new residential buildings in the composite climate of India? Concept study for the development of guidelines Volumes where the temperatures is above 26 C are filled with orange color ORIENTATION ORIENTATION TRNSYS MODEL OF TYPICAL APARTMENT OVERHANGS AND FINS WHEATHER WHEATHER FILES FILES NATURAL NATURAL VENTILATION, VENTILATION, INCLUDING INCLUDING SCHEDULES SCHEDULES AND AND CONTROLS REGULATION EXTERNAL EXTERNAL AND AND INTERNAL INTERNAL BLINDS BLINDS OUTPUTS OUTPUTS POWER POWER TEMPERATURE TEMPERATURE AIR CONDITIONERS LIGHTING DEVICES INCLUDING SCHEDULES OF USE CEILING FANS INCLUDING SCHEDULES AND REGULATION OCCUPATION SCHEDULES 28 7

8 Findings > Passive Design Solutions Findings > Passive Design Solutions PASSIVE DESIGN SOLUTIONS OPTIMISED PASSIVE DESIGN SOLUTION 29 Findings > Passive Design Solutions > Active Cooling Solutions Findings > Passive Design Solutions > Active Cooling Solutions EFFICIENT & ALTERNATIVE ACTIVE COOLING SOLUTIONS 1) EFFICIENT & ALTERNATIVE ACTIVE COOLING SOLUTIONS New generation High Performance Air Conditionner with Improved Condenser 2) AC with Evaporative Condenser, 48% savings in the cooling load 1) 2) 30 With AC with Improved Condenser, 33% savings on the cooling load High Performance Air Conditioner with Evaporative Condenser 3) Two Stage Indirect Adiabatic Cooling, 40% savings in the cooling load 3) Two stage Indirect Adiabatic Cooling

9 Findings> Passive Design Solutions > Active Cooling Solutions OPTIMISED ACTIVE COOLING SOLUTION Findings> Passive Design Solutions > Active Cooling Solutions > Combined Passive and Active Solutions COMBINATION OF ALL PASSIVE AND ACTIVE SOLUTIONS Conclusions High performance building design requires high performance software tools to be able to assess by simulation at an early design stage: o The building architectural features o o Solar protections (movable exterior or in double skin blinds) Natural ventilation. The HVAC systems Slab cooling Radiant panels High performance chillers integrating part load operation. The hybrid systems Passive and hybrid cooling systems (adiabatic, two stage/indirect adiabatic) Underground earth tunnel Vertical thermal underground heat exchangers and storage effect. Only these methods allow to compare coherently baseline projects with high performance projects options Visit the Swiss Embassy CCD (Climate Change and Development) stall about Building Energy Efficiency 9