Title: Do standard temperatures need to be constant?
Authors: Morten Ryhl-Svendsen, Lars Aasbjerg Jensen, Poul Klenz Larsen and Tim Padfield
Reference: Going Green: towards sustainability in conservation, 24 April 2009
Link: html, pdf (1.7 Mb)
Three methods of controlling relative humidity (RH) in museum stores are compared for energy use, based on data from three buildings. Full air conditioning is by far the most expensive. Next is conservation heating. Dehumidification without temperature control is by far the cheapest solution. Thermal and humidity buffers allow both conservation heating and dehumidification to operate within a safe annual temperature cycle: 15°C - 25°C for conservation heating, 10°C - 15°C for dehumidification. The saving in energy by using dehumidification rather than air conditioning is so large that the requirement for constant temperature expressed in many museum standards should be abandoned in favour of a permitted annual cycle within the range 10°C to 25°C. This will also give better chemical durability to organic materials than standards based on conditions for human comfort.