You must probably have heard some opinions about eco-friendliness of air source heat pumps. But let’s dive into numbers to see the foundation of these assertions.
Firstly, consider the Coefficient of Performance (COP) of any heat pump. To put it simply, how does it work and how effectively.
Any heat pump extracts some part of heat from outdoors and puts it where it is needed – inside your house. The same goes for cooling the apartment, not only heating it – just switch the system to work in reverse. Anyway, to put things together, it takes 1 kW of energy from your 220 outlet and brings from 2 kW to 4 (and sometimes even 5) kW inside as a portion of heat/cold. It makes COP equal to 200%-400%. For calculations, let’s take 300% as an average though it is low (losses due to uneven temperatures during the ear, heat is lost during transportation, one may have various heat pumps and so on). The effectiveness of one in your home depends on a type of a heat pump: air, water or ground (thermal) source and about a dozen of extra parameters.
Let’s move forward. Now, consider the current effectiveness of your heater working on the fossil or other fuel. For example, this study reveals the efficiency of wood-burning stoves in 80% of COP as max. And this one here tells that the stove gas burned is only 30% efficient. Let’s make the rough approximation in 60% of the COP of your current burner, just to simplify the calculations.
Secondly, let’s calculate the CO2 emissions globally to have an idea what is the current state of pollution. To do that, we take the data from the table here and extrapolate it to the entire world (guess, 2006 data is still fine if to only calculate). As we can find out, total emissions given in million metric tonnes of carbon dioxide globally in 2006 is 29,160 tonnes, from which the United Kingdom holds 585.71 million tonnes with 9.66 tonnes per year per capita (one person). According to this data, 49% of the energy in the UK was heat energy and over 34% of all energy was consumed by the individual households, with the total countrywide energy consumption equal to 907 TWh.
Thirdly, let’s calculate the increase in the efficiency of a newly installed air source heat pumps or any other type of pumps compared to your current burner. As we’ve defined upper, it is 300% vs. 60%. So, you gain 240% of COP on the output when installing a new heat pump of whatever kind. Or, 17%/83% ratio of the effectiveness of what you have now/a heat pump.
Now, if to take ONLY the UK, the shift to heat pumps can bring:
585.71*34% = 199.14 million tonnes of CO2 emissions are produced yearly by all UK’s households.
199.14/83%*17% = 40.79 million tonnes of emissions yearly may remain after all of them will install the new technology thus resulting in saving of 158.35 million tonnes of CO2 emissions yearly.
If to apply roughly the same effectiveness calculations to the entire world, we receive:
29,160/585.71*(585.71-158.35)=21,276 million tonnes or 7,883 millions of tonnes of CO2 emissions decrease (or 27% lowering)! If to correct in on the newest data of 2007 (30 million tonnes) and extrapolate it up to 2017 using the data from the table we already have mentioned even dividing the growth ratio of yearly CO2 emissions in two (receiving 6.7% of yearly growth in average), we receive that in 2017, the world CO2 emissions must be somewhere about 57,823 million tonnes (1,161.45 million tonnes in the UK). Thus, the potential worldwide economy from the heat pumps technology must be:
57.823*27% = 15,612.21 million tonnes
and in the UK solely:
1,161.45*27% = 313.59 million tonnes a year. What a whopping numbers!
But you will ask: okay, the numbers are great but what CO2 does? The answer is:
· heating up the planet making hurricanes more devastating, crops dying early from blazing temperature, millions of people having heart attacks because of heat
· acidizing the oceans killing local flora and fauna, eventually leaving us with no food sources.
Still doubt heat pumps are a must and eco-friendly?