hot water heater

The thermal resistance of copper is lower than aluminum as is its electrical resistance. This is the case with all precious metals. From lowest to best conductivity of heat and electricity; aluminum, copper, silver, gold, platinum. That is the scale of the precious industrial metals excluding high noble metal processes and alloys.



However Alum = cheaper than copper. People already pay 200-400 for a new heater. They dont want to make the price 400-600.

Originally Posted by drozenski

The thermal resistance of copper is lower than aluminum as is its electrical resistance. This is the case with all precious metals. From lowest to best conductivity of heat and electricity; aluminum, copper, silver, gold, platinum. That is the scale of the precious industrial metals excluding high noble metal processes and alloys.

However Alum = cheaper than copper. People already pay 200-400 for a new heater. They dont want to make the price 400-600.

lowest to best is as follows: Thermal Conductivity - k - (Btu/(hr oF ft))

Platinum 42
Aluminium 118
gold 182
copper 223
silver 235

As you can see, platinum is abysmal

In heat transfer, the thermal conductivity of a substance, k, is an intensive property that indicates its ability to conduct heat.

Higher is better

http://hyperphysics.phy-astr.gsu.edu...les/thrcn.html

Material Thermal conductivity
[W/(m·K)]
Air 0.025
Wood 0.04 - 0.4
Hollow Fill Fibre Insulation 0.042
Rubber 0.16
Water (liquid) 0.6
Glass 1.1
Soil 1.5
Concrete, stone 1.7
Stainless steel 12.11 ~ 45.0
Lead 35.3
Aluminium 237 (pure) ~ 120—180 (alloys)
Gold 318
Copper 401
Silver 429
Diamond 900 - 2320
Graphene (4840±440) - (5300±480)