Can I read Unit Heaters for Utilizing Reject Warm Water in Greenhouses: Control Algorithms on EtoBox?

Unit Heaters for Utilizing Reject Warm Water in Greenhouses: Control Algorithms by P. N. Walker, ; L. R. Heard, ; J. M. Carson, ; R. G. Brumfield, is a Agricultural and Biological Sciences article available to read on EtoBox.

What is Unit Heaters for Utilizing Reject Warm Water in Greenhouses: Control Algorithms about?

F OUR control algorithms were developed to modulate the flow of reject warm water to individual unit heaters in a greenhouse and to turn those units on and off. The simplest of the four algorithms turned all the units on and off simultaneously with full water flow as heat was needed in the greenhouse. The most complex algorithm selected the optimum number of units to be on and their water flow rate to meet the hourly heat requirements of the greenhouse. These algorithms were tested using a greenhouse heating computer simulation and data for a proposed greenhouse at the Bruce Mansfield power plant in western Pennsylvania. The model showed that, for a 4,000 m^ greenhouse at the conditions defined as standard, the most complex algorithm produced an annual energy savings of $2.5K more than the simplest algorithm. In a parametric study, the largest savings difference between algorithms was $5. IK when the unit cost of electricity was doubled. It was concluded that for the purpose of comparing unit heaters to other reject water heating systems, the control algorithms had a negligible effect on the energy cost savings.

Who reads Unit Heaters for Utilizing Reject Warm Water in Greenhouses: Control Algorithms?

Author

P. N. Walker, ; L. R. Heard, ; J. M. Carson, ; R. G. Brumfield,

Publisher

American Society of Agricultural and Biological Engineers; American Society of Agricultural Engineers; American Society of Agricultural and Biological Engineers (ASABE) (ISSN 0001-2351)

Published

1987

Language

EN

Field

Agricultural and Biological Sciences (Physical Sciences)