Let’s relate the figures given in Desk Study 2 to some more understandable numbers. Carbon emissions and money.
Let’s say you own the example house in Desk Study 2 and have installed our thermally broken lintel. You’ve reduced your heat loss by 4.65W/K on the 5m opening, congratulations! Let’s turn that into reduced carbon emissions.
The average UK temperature is a daily high of 13oC and daily low of 6oC. The average living room temperature is 21oC, but say you reduce this to 18oC for 8 hours at night.
For simplicity, we’ll use an 8oC temperature difference during the day and 12oC temperature difference for 8 hours during the night. Multiplying these values by the 4.65W/K reduced heat loss shows you’ve saved 1041.6W in heat for the day. Multiply this by the 365 days and you’ve saved 380184W (or 380.2kW) for the year. Not bad.
Gas is often measured in BTUs (British Thermal Units), and there are 3.41BTU to 1W. This makes the BTU saving just shy of 1.3 million BTUs.
From a quick online search, we can see that burning natural gas results in 117lbs (53.1kg) per million BTUs.
Therefore, by choosing our lintel you’ve reduced CO2 emissions by 68.8kg per year for the life of the property. That’s the same as driving over 300 miles in the average car, which for the average car is the same as not driving it for two weeks every year!
Not only that, but at the average cost of gas being 10.4p per kWh the lintel will save £39.54 a year from your energy bill. The lintel more than pays for itself over its lifetime.
Stated values are as of the date of writing, and are found from online searches which may not be verified.