With the summer heat and humidity upon us, most homes and businesses rely heavily on air conditioning to stay cool. High temperatures are often accompanied by a humidex rating which indicates the effect of humidity on comfort levels.
So how did people deal with these temperatures before air conditioning was widely available? The answer is simple – homes and businesses were built differently. Specifically, they were built using heavy materials including brick, clay, plaster and concrete.
The ERC and this cave have a lot in common.
The mass of these materials acts as a thermal battery. In simple terms, these types of materials imitate a cave – heavy and coupled to the ground, allowing for very slow temperature changes so the space doesn’t react to sudden spikes in outdoor temperatures. If you have a basement, you’d likely notice the difference in temperature between the ground floor and the lower level as the concrete acts as a buffer against the outdoor temperatures.
The Earth Rangers Centre takes this same principle and integrates it into the core of its heating and cooling strategy. The effects noted above are passive, while the ERC deliberately controls the temperature of the thermal mass with radiant tubing and ground-coupled heat exchange (or a geothermal system). There are many advantages to this method, namely, dramatic energy efficiency and higher comfort levels when compared to typical forced air heating and cooling – and the bonus, no drafts!
If outdoor humidity levels allow, we can “free cool” the building, directly exchanging summer heat absorbed by the building and transferring it to cool ground beneath the parking lot. This requires only 18 horsepower in pumping energy to cool the entire ERC – saving up to $175 per day in summer cooling costs.
This material choice and cooling strategy is not without some compromise, but when looked at over the lifecycle of the building, this choice makes sense. Cement, the glue in concrete, is an energy intensive material to create. The initial investment in energy is offset by the energy efficiency gains attained by the building throughout its life. Also, the aggregates that make up the majority of the concrete’s constituents are locally sourced, and come from small areas that minimize resource impacts on local wildlife.
Habitat loss and fragmentation is arguably the greatest threat facing biodiversity (Caro and Sherman 2011, Sala et al. 2000). If we can learn to confine areas of resource extraction and minimize the need for additional raw materials by reusing already manufactured goods, wildlife everywhere benefits.
The Dufferin Aggregates Milton Quarry exceeds global best practices for rehabilitation.
All of these reasons are why the ERC is a very heavy building, and how we keep cool throughout the summer months. Consider sleeping in your basement to save air conditioning energy!
Sources:
Caro T and PW Sherman (2011). Endangered species and a threatened discipline: behavioural ecology. Trends in Ecology and Evolution 26:111-118.
Sala OE, FS Chapin III, JJ Armesto, E Berlow, J Bloomfield, R Dirzo, E Huber-Sanwald, LF Huenneke, RB Jackson, A Kinzig, R Leemans, DM Lodge, HA Mooney, M Oesterheld, NL Poff, MT Sykes, BH Walker, M Walker, and DH Wall (2000). Global biodiversity scenarios for the year 2100. Science 287:1770-1774.