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I was looking at the picture you used for the article, and it reminded me that the Colliseum was mostly built of tile with a concrete mortar. The reason why some of it is missing is that the tiles were taken for use elsewhere. This is the reason why a lot of the old Roman buildings are in disrepair.
The Pantheon, which is nearby but elsewhere in Rome, is a compression structure, not needing much tensile strength. If built properly, most compressive structures last nearly forever. Tensile structures, which have a tendency to 'pull apart' are better built of other materials, but often concrete is used because it is cheaper.
The first iron railway bridges failed, as iron also has a poor tensile strength. Arches provide compression along the arch, which allows stone and concrete structures made that way to last a very long time. Flat spans of un-reinforced concrete and stone are very weak.
For my current 'cool room' I have a two inch thich piece of sheet styrofoam (from the building supply store) mostly sealing the space behind the curtain. Takes the 'R' value of the window from about two to about twelve. As windows let the most heat in, this keeps the room cooler. The drawback is that it also stops most of the light comming in, but that would not be an issue most of the time in a bedroom.
Most of the reinforced concrete used in our roads, bridges, and buildings, is reinforced with cheap steel rebar. The problem is that the steel expands as it oxidizes. That cracks the cement from the inside. There is a new carbon fiber 'rebar' that does not have this problem, and will allow the concrete to last much longer in the prescence of any oxidixing agent, including sea water.
While not built without oil, My electric car does not need oil the same way a 'standard' internal combustion engine does. Fossil oil can be repladced with plant and animal sources in many places, as WD40 is actually a fish oil.
This is an old bug-a-boo. If the equipment was made in the last 5 years, and have a 'energy star' rating, the equipment will use very little power at standby. If you have a concern, buy a kill-a-watt meter, and see how much current the device draws. My current computer and large screen TV use less than 2 watts at standby. The new DVR does draw about 6 watts, but still no where near 10%.
Of course you money may vary….
While the prices are still higher, LED lighting is more efficient and should last even longer than CF. Currently my utility has a rebate program that makes the costs nearly identical.
If natural gas is available, it is less expensive than propane for heating, in large part due to the fact that natural gas is usually plumbed into a neighborhood, and therefore has no additional delivery expense. Changing from one source to the other is relatively easy, as the usually only parts that have to be changed are the pressure restrictors and flow limiters. Both propane and NG heating will normally be able to run during an electric outage, but the blowers that move the heat around may not.
In most parts of the country that have NG, the pumping stations have NG generators as a backup to keep the gas flowing. Unless the temperatures get really cold, the usual issues are demand related, and not enough supply. For propane, the tank needs to stay above the liquification temperature, and if it gets too cold outside, the unit that converts the liquid propane to gas can stop working, but there is usually a very small heater that makes sure that situation does not happen.
Show me an indepently validated study….
Wendy, I went for the 'spray in' reflective film in my attic, and the summer temperatures up there have gone down by about twenty or thirty degrees. While not 'sexy' these improvments, like insulation, work for as long as you own the house.
I use a heat pump for heating and cooling, as wood is hard to come by here in the (southern nevada) desert. I also put in solar panels, which cut my electric bill in half. Now that I have an electric car I expect my electric use will go up again, but I am looking at a few more solar panels to get to the mythical 'net zero".