4 ms·
A lot of "wasted" heat is not wasted. For example, if you extract the energy on the return channel, my gas boiler has to work harder to re-heat..
by tiku 5y ago
A lot of "wasted" heat is not wasted. For example, if you extract the energy on the return channel, my gas boiler has to work harder to re-heat..
- varjag 5y agoThe energy that is radiated/convected away from your return channel never makes it back to your boiler.
- OJFord 5y agoBut if take it away, cooling the pipe, more will make it out of the water and into the pipe (and so not back to the boiler). That's no different to turning up your radiator.
- benlumen 5y agoIt still should radiate into the house, helping to bring the temperature up to the thermostat point. If you're capturing any of that heat and converting it for any reason, your boiler's simply going to have to work harder to do its job. It's the first law of thermodynamics, isn't it? I'm not a physicist.
- cma 5y agoBut if you have a heatpump instead of boiler it maybe doesn't have to work as much harder.
- Firadeoclus 5y agoIt depends on what the converted energy is used for. If you use it to power a device in the house then it's quite likely most of that energy will end up as heat in the house again.
- lolc 5y agoIt can make sense to combine stoves used for heating with peltier elements. When the heat is used at lower temperature than the combustion, you can get electricity on the exchange. So you run your boiler at 105% normal capacity and extract 5% electricity. This generates electricity at the price of gas. Of course, your boiler must have the extra capacity, and the additional components are an investment.
- IanCal 5y agoIt's not always so straight forward. You would want your return to be lower than about 55C for a condensing boiler otherwise they're a lot less efficient.