http://www.youtube.com/watch?v=qybUFnY7Y8w
Reminiscent of the Honda Accord Ad "The Cog"
Sunday, 21 March 2010
Wednesday, 10 March 2010
Tuesday, 9 March 2010
Saturday, 6 March 2010
Global Not Warming
The worst freeze for over 30 years has affected the Baltic, trapping many ships in the ice.
http://www.telegraph.co.uk/news/worldnews/europe/sweden/7374495/Ships-stranded-for-hours-in-Baltic-Sea-ice-freed.html
http://www.telegraph.co.uk/news/worldnews/europe/sweden/7374495/Ships-stranded-for-hours-in-Baltic-Sea-ice-freed.html
Monday, 1 March 2010
Washing Prescott's Smalls
Oxymoron of the month from Iain Dale. And it's not yet March 2nd.
http://iaindale.blogspot.com/2010/02/washing-prescotts-smalls.html#links
http://iaindale.blogspot.com/2010/02/washing-prescotts-smalls.html#links
Saturday, 27 February 2010
Heating Appliance-Efficiency Con
To deliberately mislead consumers, appliance manufacturers quote their appliances' efficiency at Net cv (calorific value) or ncv. This enables them to quote a higher number, & so con purchasers into thinking their energy use will be less than it actually will be.
A manufacturer that states his appliance is, for example, 95% efficient (ncv) misleads a purchaser into thinking that only 5% of the fuel / energy is wasted into the flue.
Not so.
Net cv is only a theoretical figure. It is thermodynamically impossibility to buy fuel / energy at Net cv, so by definition, all energy is supplied at Gross cv. The relationship between Net & Gross cv (in the UK for Natural Gas) is that Net cv is 1.11 x Gross cv.
e.g. An appliance that is quoted as 95% efficient at Net cv has a Gross efficiency of only 85.595%. In other words, a consumer who buys 100 units of fuel / energy, gets not 95 but only 85.595 units of useable heat.
The fact that manufacturers can quote efficiencies at Net cv means they can quote a figure greater than 100% for modern condensing boilers. (Could be approx 104% Net cv.) Hands up those who thought that at 104% efficiency, that boiler gave them 4% more heat than they purchased.
That boiler quoted at 104% Net cv efficiency is only 93.704% efficient and loses 6.296% of energy by case & flue losses.
A manufacturer that states his appliance is, for example, 95% efficient (ncv) misleads a purchaser into thinking that only 5% of the fuel / energy is wasted into the flue.
Not so.
Net cv is only a theoretical figure. It is thermodynamically impossibility to buy fuel / energy at Net cv, so by definition, all energy is supplied at Gross cv. The relationship between Net & Gross cv (in the UK for Natural Gas) is that Net cv is 1.11 x Gross cv.
e.g. An appliance that is quoted as 95% efficient at Net cv has a Gross efficiency of only 85.595%. In other words, a consumer who buys 100 units of fuel / energy, gets not 95 but only 85.595 units of useable heat.
The fact that manufacturers can quote efficiencies at Net cv means they can quote a figure greater than 100% for modern condensing boilers. (Could be approx 104% Net cv.) Hands up those who thought that at 104% efficiency, that boiler gave them 4% more heat than they purchased.
That boiler quoted at 104% Net cv efficiency is only 93.704% efficient and loses 6.296% of energy by case & flue losses.
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