Biomass vs heat pumps

I was Tik-Toking, as you do. I really shouldn’t be, because I’m ancient, mid fifties, if you must know, but I saw this guy talking about AI. It sounded interesting and to be completely honest, a bit worrying. You can effectively get this AI to do your homework for you. Tell it to write a thousand words on a subject and it’ll spit out the text in a minute or two. If you wanted to cheat, you could get this thing to write an essay for you and you get an A+ for little to no effort.

So, it was past gin ‘o’ clock on a Friday and I decided to put this instruction into it: Compare the relative merits of biomass and air source heat pumps. Immediately, it started writing, about as fast as my wife can type, and it came out with this:

Air source heat pumps (ASHPs) and biomass boilers are both popular renewable heating options, but they have different merits depending on your needs and circumstances. Here are some key factors to consider when comparing the two:

Ultimately, the choice between an ASHP and biomass boiler will depend on your specific needs and circumstances, including your budget, location, and heating requirements. It’s worth consulting with a professional heating engineer to determine which option is best for your situation.

  1. Cost:

    ASHPs tend to have a higher upfront cost than biomass boilers, but they are generally cheaper to install and maintain over time. Biomass boilers can be cheaper to run if you have access to low-cost wood fuel, but if you have to buy fuel, the cost can be higher than using electricity to power an ASHP.
  2. Efficiency:

    ASHPs are typically more efficient than biomass boilers, meaning they require less energy to produce the same amount of heat. This is because they extract heat from the air outside and concentrate it to heat your home, while biomass boilers burn wood to produce heat. However, biomass boilers can have higher efficiency if they are well-designed and maintained properly.
  3. Renewable energy source:

    Both ASHPs and biomass boilers use renewable energy sources, which is a major advantage over traditional fossil fuel-based heating systems. However, the sustainability of the fuel used in biomass boilers can be a concern, as some wood fuel sources may not be sustainable.
  4. Noise:

    ASHPs tend to be quieter than biomass boilers, which can be important if you live in a built-up area or have close neighbours.
  5. Carbon emissions:

    Both ASHPs and biomass boilers produce fewer carbon emissions than traditional fossil fuel-based heating systems. However, the emissions from biomass boilers can vary depending on the type of wood fuel used and how it is sourced and processed.

My first reaction was that it had got most of the facts wrong.

For instance, Point 1, ASHPs are generally cheaper than biomass to install, though in most instances the householder has to increase the size of all their radiators by 30% for ASHPs, so the cost of doing that ramps it up, but if you have underfloor heating nothing changes, so it works out very cheap to buy.

Point 2 is arguable, because it depends upon the type of biomass boiler, what the fuel is and where it comes from. If you chopped down a tree in your back garden, or if you’re lucky enough to have a woodland, and you cut it down with an axe and let it season for a year before you chopped it into logs, it’s as green in save the earth terms as you can get. If you were running your boiler on pellets that were made in Belarus and transported to the UK on a bulk tanker running on crude oil, not so much. But if your ASHP (most are made in China and Japan and transported to the UK on bulk freighters running on crude oil) is running on electricity from the grid, up to 60% of the power generated can be lost in transmission, and at least 50% of our power generation still comes from fossil fuels and probably 5 or 10% from nuclear. Two thirds of the heat is free, but the refrigerant in the ASHP has a greenhouse and ozone depleting effect many hundreds or even thousands of times worse than oil or natural gas, so… contentious, shall we say?

Point 3, well, the first part I’ve gone into above, but the second part is incorrect, in the UK at least. All the fuels on the BSL list have to be sustainably sourced, so if you’re claiming RHI this is a condition of receiving it. As a result, most people buy from the BSL suppliers.

Point 4. If you have a biomass in an outbuilding or garage, or even a utility room, the chances are you won’t hear it at all. If you’ve got a cheap pellet boiler with a fire front in your living room, they are a bit noisy. Similar to having an oil boiler sat in the lounge with you. Heat pumps generally sound like industrial freezers and there’s actually a decibel limit that you can allow for at doors and windows. They’re noisy. A low pitched thrum whenever the thing is on. But if it’s sat outside and you’re watching telly, you probably think it’s quiet, because you’re unlikely to hear it through the outside walls, as long as your installer put it far enough away from your windows.

Point 5. This is true to some extent. If you’re burning wet wood, which is a waste of everybody’s time and money, the emissions will not be great, but they’ll still be better than burning natural gas, if we’re talking about carbon dioxide, which is 300% more polluting than a biomass boiler that is burning correctly. Particulate matter is something else, but if you buy a good quality biomass with an electrostatic precipitator in the flue, or one that filters the fumes through the fuel before it’s burnt, there’s no particulates to talk of. But let’s talk about making the steel for these items in blast furnaces. Many ASHPs are made in China, where they are opening a new coal fired power station every week and they’re running their blast furnaces on gas. Most of our solar panels are made there too, and I honestly wonder whether they’ll actually take more energy to produce than they’ll ever make in their lifetime (they’re supposed to within 3 years in most cases). They’ll be packed up in unrecyclable plastic and shipped to us on, you guessed it, bulk freighters running on crude oil.

In summary… *shrugs* Glad I’m not a politician. Glad I’m not young, because the internet is full of so much disinformation, and AI looks set to make it worse.