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What is energy saving?
I think this is a subject for debate. Energy saving is very different to money saving because of the vast difference between costs of gas, electric and oil but some of that is due to losses in converting gas to electricity so not clearly defined.
Energy is used for lighting and heating of the home. The heating of the home is paramount in this discussion. There are two basic methods. Convection where the air is heated and circulated around the home and Radiation when heat is transferred from the heater direct to the body within it’s range.
The problem with Radiation is how to measure as most thermostats are white in colour and so reflect radiated heat.
However in most homes the temperature set can be reduced by 2 degrees where radiated heat is used.
What we are looking at is how much heat leaves the house with each system and what energy is required to cool the house.
During the summer the less heat produced the better. But during the winter one is only looking at unwanted heat. So for example in the summer a CFU for lighting must save energy but during the winter since the heat is not only wanted but with tungsten lamps radiated is could well be it saves energy by using tungsten rather than CFU’s?
Of course it will depend on how much. A kitchen with 10 tungsten 50mm down lighters is very likely to use more energy even with a radiator thermostatic valve than a kitchen using discharge lighting (florescent) but again it would also depend on what was used to cook with.
Microwave ovens and induction hobs put most of the energy into the food. The other extreme with gas ovens and gas hobs likely also huge extractor fans will be required not only to remove the heat but also all the moisture generated.
This also applies to items like the tumble drier when the type using a heat pump does not remove any hot air from the room but the type with a heater is not only pumping out hot air from the tumble drier but also air heated by central heating so in turn drawing in cold air from outside.
As we start to consider the heating options it becomes apparent that winter and summer are very different and if we look at countries in the warmer areas we see the use of CFU’s is very high where then are more worried about keeping the home cool than in keeping it warm. So in the UK Scotland must be very different to England when considering if CFU’s rather than tungsten should be used for lighting.
I asked the energy saving trust for information but is seems that integrated testing has not been carried out and although they admit the use of CFU’s in Scotland will produce vey different figures to using CFU’s in England they have no information as to what that difference is.
It seems that each item is taken in isolation and no account is taken as to for example how much the heat given off from a tungsten lamp will reduce the temperature required to feel comfortable. I would estimate around 2 degrees.
So the question is how much do we consider the individual power requirements to how much the overall power requirements? In other words is a tungsten lamps at 60W gives us 10W of light and 40W of heat and means we reduce the thermostat setting by 10 degrees is it saving or wasting energy?
Does blowing out pre-heated air with a tumble drier save or waist energy compared with a tumble drier that does not blow air out side? (And we are not considering the dangers of producing a negative pressure and drawing in combustion gasses from gas fires).
The same question as to gas hobs to induction hobs where with the former extractors are required to remove both heat and moisture produced by the gas. The same to lesser extent with microwave and other type of ovens again any gas oven is producing moisture as well as heat.
Of course there is a consideration as to if moisture is wanted or not? Many consider the moisture produced with a gas oven improves the produce produced!
But question is energy saving not quality of light or food so what is the consensuses do energy saving devices really save energy or is it just a marketing measure?
I think this is a subject for debate. Energy saving is very different to money saving because of the vast difference between costs of gas, electric and oil but some of that is due to losses in converting gas to electricity so not clearly defined.
Energy is used for lighting and heating of the home. The heating of the home is paramount in this discussion. There are two basic methods. Convection where the air is heated and circulated around the home and Radiation when heat is transferred from the heater direct to the body within it’s range.
The problem with Radiation is how to measure as most thermostats are white in colour and so reflect radiated heat.
However in most homes the temperature set can be reduced by 2 degrees where radiated heat is used.
What we are looking at is how much heat leaves the house with each system and what energy is required to cool the house.
During the summer the less heat produced the better. But during the winter one is only looking at unwanted heat. So for example in the summer a CFU for lighting must save energy but during the winter since the heat is not only wanted but with tungsten lamps radiated is could well be it saves energy by using tungsten rather than CFU’s?
Of course it will depend on how much. A kitchen with 10 tungsten 50mm down lighters is very likely to use more energy even with a radiator thermostatic valve than a kitchen using discharge lighting (florescent) but again it would also depend on what was used to cook with.
Microwave ovens and induction hobs put most of the energy into the food. The other extreme with gas ovens and gas hobs likely also huge extractor fans will be required not only to remove the heat but also all the moisture generated.
This also applies to items like the tumble drier when the type using a heat pump does not remove any hot air from the room but the type with a heater is not only pumping out hot air from the tumble drier but also air heated by central heating so in turn drawing in cold air from outside.
As we start to consider the heating options it becomes apparent that winter and summer are very different and if we look at countries in the warmer areas we see the use of CFU’s is very high where then are more worried about keeping the home cool than in keeping it warm. So in the UK Scotland must be very different to England when considering if CFU’s rather than tungsten should be used for lighting.
I asked the energy saving trust for information but is seems that integrated testing has not been carried out and although they admit the use of CFU’s in Scotland will produce vey different figures to using CFU’s in England they have no information as to what that difference is.
It seems that each item is taken in isolation and no account is taken as to for example how much the heat given off from a tungsten lamp will reduce the temperature required to feel comfortable. I would estimate around 2 degrees.
So the question is how much do we consider the individual power requirements to how much the overall power requirements? In other words is a tungsten lamps at 60W gives us 10W of light and 40W of heat and means we reduce the thermostat setting by 10 degrees is it saving or wasting energy?
Does blowing out pre-heated air with a tumble drier save or waist energy compared with a tumble drier that does not blow air out side? (And we are not considering the dangers of producing a negative pressure and drawing in combustion gasses from gas fires).
The same question as to gas hobs to induction hobs where with the former extractors are required to remove both heat and moisture produced by the gas. The same to lesser extent with microwave and other type of ovens again any gas oven is producing moisture as well as heat.
Of course there is a consideration as to if moisture is wanted or not? Many consider the moisture produced with a gas oven improves the produce produced!
But question is energy saving not quality of light or food so what is the consensuses do energy saving devices really save energy or is it just a marketing measure?
