Low Exergy HeatRrecovery for Sustainable Indoor Agriculture

Anthony Goncalves
t3e Industrial research chair, École de technologie supårieure, Montråal, Canada

Daniel Rousse
t3e Industrial research chair, École de technologie supårieure, Montråal, Canada

Julien Milot
Energy Solutions Associates, Låvis, Canada

Ladda ner artikelhttp://dx.doi.org/10.3384/ecp11057788

Ingår i: World Renewable Energy Congress - Sweden; 8-13 May; 2011; Linköping; Sweden

Linköping Electronic Conference Proceedings 57:6, s. 788-795

Visa mer +

Publicerad: 2011-11-03

ISBN: 978-91-7393-070-3

ISSN: 1650-3686 (tryckt), 1650-3740 (online)


With improved greenhouses; farmers have to ventilate. An air-to-air multi-tube counter flow heat exchanger unit was installed in a greenhouse used for the experimental cultivation of hydroponic tomatoes and cucumbers. This 24m long unit involves a 12” O.D. external shell used to exhaust moist air and five inner tubes to bring fresh air inside. The tests; carried out between March and May in a 576 m3 enclosure; demonstrated that average efficiencies of ?=84% and ?=78% were obtainable with air volumetric exchanges rates of 0.5 and 0.9 change per hour; respectively. Latent heat was found to play a major role in the overall heat transfer; contributing about 40% of the total energy exchanged in some situations. The exchanger could be buried underneath the ground or suspended above the crops. The unit made of plastic is durable; rot and rust resistant; affordable; and is ice and frost compliant. A pre commercial implementation with an improved design is now considered in collaboration with Gaz Metro. This paper presents the original prototype that help in reducing the consumption of natural gas; fuel; bunker; or propane.


Heat exchanger; Latent heat recover; Sensible heat recovery; Plastic


[1] E. Brundrett; T.J. Jewett; and R. Quist; Evaluation of polytube heat exchangers for greenhouse ventilation". Acta-horticultarae; 148; 1984; pp.49-55.

[2] J.N. Walker and D.J. Cotter; Condensation and resultant humidity in greenhouses durng cold weather; Trans. ASEA; 11(2); 1968; pp.263-266. doi: 10.13031/2013.39387.

[3] D.J.Cotter and R.T. Seay; The effect of circulating air on the environment and tomato growth response in a plastic greehouse; Roc. ASHS; 77; 1961; pp.345-342.

[4] SPSQ.; Ékiloserre; Projet d’amélioration de la situation énergétique de l’industrie serricole québécoise; Rapport Final; Syndicat des Producteurs en Serre du Québec; St-Hyacinthe; 1995.

[5] D. DeHalleux; and L. Gauthier; Consommation énergétique due à la déshumidification des serres au Québec; Université Laval; Québec; 1995.

[6] BNQ.; Norme 3624-115 (91-08-01); Tubes annelés flexibles et raccords en thermoplastique pour le drainage des sols; Bureau de Normalisation du Québec; Québec; 1991.

[7] BNQ.; Norme 3624-120 (90-02-20); Tuyaux annelés à l’intérieur lisse et raccords en plastiques Pe ou PP pour l’évacuation des eaux pluviales; Bureau de Normalisation du Québec; Québec; 1990.

[8] A. Bejan; Convection Heat Transfer; 2nd ed.; Wiley; New-York; 1993

[9] V. Gnielinski; New Equations for Heat and Mass Transfer in Turbulent Pipe and Channel Flow; Int. Chem. Eng.; vol.16; 1976; pp.359-368.

[10] V. Gnielinski; Forced Convection in Ducts; in G.F.Hewitt (ed.); Handbook of Heat Exchanger Design; Begell House; NY; 1952; section 2.5.1-5.

[11] H. Hausen; Darstellung des Wärmeüberganges in Rohren durch verallgemeinerte Potenzbezeihungen; Z. Ver. Dtsch. Ing. Beiheft Verfahrenstech.; vol.4; 1943; pp.91-134.

[12] H. Hausen; Heat Transfer in Counterflow; Parallel Flow and Cross Flow; McGraw-Hill; USA; 1983.

Citeringar i Crossref