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Energy Saver (?): Heating Energy Methods
(continued ...) Another story is related to a business trip to Ireland. The climate there rarely puts them below freezing but heating is needed on occasion. There are some modern buildings but there are also many buildings and homes that have been around for hundreds of years. These fantastic older buildings don't have furnaces, heat pumps or boilers. Rather, they are heated with fireplaces fueled with coal. Coal makes for an incredibly hot fire compared to my experiences with a wood fueled fire place. Just a few small clumps put out some serious heat. A coal fireplace was a very nice treat while enjoying a pint at a local pub. Never-the-less, it is still a fireplace and thus a huge energy waster. See the article on fireplaces for an expanded discussion of fireplaces.
Yet another story is from travels in Europe. The world wars of sixty plus years ago destroyed and damaged many buildings. How unfortunate that is in so many ways. I have been in modern buildings there but there a few I visited were some 600 years old. Some of those ancient buildings I visited had walls of stone that were three feet (1 meter) thick. If solid, that is an R-value of about 2.9 (using 0.8 per inch) but there could have been an air gap inside the wall assembly. Still air is a great insulator. That's actually how fiberglass and other insulation products work but more on that later. If there was an air gap of about 3 inches (8 cm) inside the wall and making a whole bunch of other assumptions, the overall wall could have had an R-value approaching 5.75. Not bad for 600 year old building technology. These buildings were heated with some arrangement of fireplaces. Some rooms had no provisions for heat. I expect during colder seasons, they may not have used some rooms.