Díaz de Garayo, Sergio

Profile Picture

Email Address

person.page.identifierURI

https://academica-e.unavarra.es/handle/2454/53651

Birth Date

Job Title

Last Name

Díaz de Garayo

First Name

Sergio

person.page.departamento

Ingeniería

person.page.instituteName

ORCID

0000-0002-7849-9353

person.page.observainves

1173395

person.page.upna

812826

Name

Filters

2019 - 201912020 - 20242
Reset filters

Settings

Subject: nZEB ×

Search Results

Now showing 1 - 3 of 3
  • Thumbnail Image
    PublicationOpen Access
    Heat pipes thermal performance for a reversible thermoelectric cooler-heat pump for a nZEB
    (Elsevier, 2019) Aranguren Garacochea, Patricia; Díaz de Garayo, Sergio; Martínez Echeverri, Álvaro; Araiz Vega, Miguel; Astrain Ulibarrena, David; Ingeniaritza; Institute of Smart Cities - ISC; Ingeniería
    The nZEB standards reduce the energy demand of these buildings to a minimum, obtaining this little energy from renewable resources. Taking these aspect into consideration, a thermoelectric cooler-heat pump is proposed to achieve the comfort temperature along the whole year. The same device can provide heat in winter and it can cool down the buildings in summer just by switching the voltage supply polarity. Heat pipes are studied to work on both sides of the thermoelectric modules in order to optimize the heat transfer as these devices present really good thermal resistances and they can work in any position. However, they present pretty different thermal resistances if they work on the cold or on the hot side of the modules. A methodology to thermally characterize these heat exchangers working in both orientations is proposed and a validated computational model is developed to optimize the thermoelectric cooler-heat pump for a nZEB application. The number of thermoelectric modules, the position of the device, the ambient temperature and the air mass flow determine the operation and consequently they need to be studied in order to optimize the application.
  • Thumbnail Image
    PublicationOpen Access
    Design and analysis of a two-stage cascade system for heating and hot water production in nearly zero-energy buildings using thermoelectric technology
    (MDPI, 2024-12-16) Ordóñez, Javier ; Díaz de Garayo, Sergio; Martínez Echeverri, Álvaro; Algarra Pérez, Fernando; Astrain Ulibarrena, David; Ingeniería; Ingeniaritza; Institute of Smart Cities - ISC; Gobierno de Navarra / Nafarroako Gobernua
    This paper proposes an innovative system that integrates two thermoelectric heat pumps (one air–water and the other water–water) with two thermal storage tanks at different temperatures to provide heating and domestic hot water to a 73.3 m2 passive-house-certified dwelling in Pamplona (Spain). The air–water thermoelectric heat pump extracts heat from the ambient air and provides heat to a tank at intermediate temperature, which supplies water to a radiant floor. The water–water heat pump takes heat from this tank and provides heat to the other tank, at higher temperature, which supplies domestic hot water. The system performance and comfort conditions are computationally analyzed during the month of January under the climate of Pamplona and under different European climates. The COP of the system lays between 1.3 and 1.7, depending on the climate, because of the low COP of the air–water thermoelectric heat pump. However, it is able to provide water for the radiant floor and to maintain the temperature of the dwelling above 20 °C 99.8% of the time. Moreover, it provides domestic hot water at a temperature above 43 °C 99.9% of the time. Noteworthy is the fact that the water–water heat pump presents a COP close to 4, which opens up the possibilities of working in combination with more efficient heat pumps for the first stage.
  • Thumbnail Image
    PublicationOpen Access
    Thermoelectric heating and air conditioning with double flux ventilation in passive houses
    (2022) Díaz de Garayo, Sergio; Astrain Ulibarrena, David; Martínez Echeverri, Álvaro; Ingeniería; Ingeniaritza; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa; Gobierno de Navarra / Nafarroako Gobernua
    Esta tesis propone el uso de bombas de calor basadas en termoelectricidad, cuyas ventajas competitivas se basan fundamentalmente en la ausencia de partes móviles y de refrigerantes. Concretamente, esta tesis se centra en el diseño y construcción de un dispositivo de bomba de calor air-aire integrado con la ventilación de doble flujo en viviendas con una superficie inferior a 100 m2 y una envolvente de alta eficiencia energética tipo ‘Passive House’, donde la reducida carga de calefacción (<10 W/m2) permite climatizar el espacio con el caudal de aire de ventilación, aprovechando el calor residual del aire renovado. Los resultados demuestran que la termolectricidad puede resultar una alternativa real a la construcción de bombas de calor para la climatización de viviendas ‘Passive House’, dada la gran cantidad de ventajas (sistema silencioso, robusto, diseño ligero y fácilmente instalable en techos falsos, fácil regulación, integrabilidad con instalaciones fotovoltaicas y potencial de ahorro en los costes de fabricación), comparado con su menor eficiencia, fácilmente compensable con el incremento de la producción fotovoltaica integrada en el edificio.