8
votes
Accepted
How much energy would it cost to stabilize 2 tons of water at 70 degrees?
The stabilisation energy rate will be exactly exactly equal to the rate at which energy is lost.
Assuming the tank is closed, so there are no evaporative losses, there are two other ways energy is ...
- 14.8k
6
votes
How does one calculate the wattage of a biomass fired water heater
Water has a heat capacity of 4.1814 J/g which means that 1 gram of water requires 4.1814 Joules of heat to increase 1°C. The definition of Watt is Joules / second so the formula you need is:
heat ...
- 14.6k
6
votes
Reuse waste heat from air conditioning
The problem of heating water from waste heat from air conditioning is that the water needs to be heated to at least 60 degrees Celsius to prevent Legionella bacterium from growing. On the other hand, ...
- 5,249
5
votes
Accepted
Temperature for hot water cylinder
Yes, higher thermostat temperatures mean more electricity consumption. Also your thermostat manual is right, bacteria growth is a valid concern.
The ideal conditions for the Legionella bacteria to ...
- 14.6k
4
votes
How can I decarbonise my domestic heating, given severe physical constraints?
The glib answer is to use less energy.
The best way of doing that is fixing the fabric of the house - massively increasing insulation, massively decreasing air permeability (and as a result fitting ...
- 141
3
votes
Accepted
How can I conserve energy and water in my bathroom?
Others have already suggested low flow fixtures and reducing water usage, but here are a few other ideas, from least to most expensive:
Turn down your water heater. The U.S. Department of Energy ...
- 12k
3
votes
How much more efficient is boiling water with a lid?
TL;DR: power saving with a lid comes from the fact that you can use a lower power-mode on
your cookstove. Energy used to bring the water to the boiling point is roughly the same with or without the ...
- 280
3
votes
Feeding hotwater into modern appliances
I am not aware of any modern washing machines (at least in the UK) that still have a hot water feed. One reason is that modern machines don't actually use that much water, so even if you had it ...
- 387
3
votes
Heating water with compost
For everyone to know, the process was developed by and is now known by the name of Jean Pain Composting process. The man used the technique to heat water for house heating and hot water needs.
[...]...
- 1,437
2
votes
Running boiler intake along chimney for preheating
I'm glad you found that the extra information about the problems of cooling down your chimney pipe. That is the first point I was going to make in this answer (and I'll make it anyway). You do not ...
- 1,654
2
votes
Shall I boil water with a water boiler (cooker) or with a pot?
Put the broccoli in a microwave safe bowl with a few tablespoons of water, cover the bowl with a microwave safe top (ideally maybe a glass lid, but if plastic, don't let it touch the food!).
Then ...
- 21
2
votes
Does a solar thermal hot water system make sense for my home?
With today's prices, it's cheaper to install PV panels and generate electricity, then just use a standard electric water heater.
This has the advantage that it actually works better in the winter ...
- 31
2
votes
Accepted
Most energy-efficient way to keep my pipes from freezing without tearing up walls/floor?
Leave the faucet open at a trickle. From Consumer Reports:
Let the cold water drip from a faucet served by exposed pipes. Running water through the pipe—even at a trickle—helps prevent pipes from ...
- 12k
2
votes
Which energy sources will replace fossil fuels for heating homes in cold climates?
In terms of efficiently using sun's energy. Let's not forget passive solar.
With no mechanical parts to break, a sufficiently heavy or phase change thermal mass can go a long way when the house is ...
- 21
2
votes
Which energy sources will replace fossil fuels for heating homes in cold climates?
There's an interesting summary of the situation in the UK here.
In short, the most widespread option is likely to be heat pumps, despite some significant disadvantages, such as cost, and that fact ...
- 387
2
votes
How much coil do I need to heat a given length of pipe (as a function of x,y,z)?
I've used them. I've never been happy with them. If you do use them you need to follow these rules:
If you wrap them you must have the wraps evenly spaced. You can't have 3 turns per foot at one ...
- 7,247
1
vote
Accepted
How to keep my tankless water heater safe in a cold room?
Since the water heater is not on an exterior wall, it is likely that the pipes you mention which do pass through the exterior wall would freeze before pipes inside the heater do. This would cause ...
- 12k
1
vote
Accepted
Should I turn off my Gas Water Heater if I will be gone for 3 days?
At any given thermostat setting, for any given amount of time, it will be more efficient for your gas water heater to be turned off than to be turned on.
As described by Newton's law of cooling, the ...
- 1,654
1
vote
What is the most sustainable choice for a domestic hot water system in temperate, coastal Australia?
Electric Tank
The technology is tried and tested, and the tanks are cheap. Take the money you save and increase the size of your planned solar array. Tilt your (north) array string a little bit ...
- 2,889
1
vote
What is the most sustainable choice for a domestic hot water system in temperate, coastal Australia?
Heat pump water heaters are powered by externalities
A heat-pump water heater warms water by chilling the room the water heater is in. On a sweltering hot day, that helps air conditioning load ...
1
vote
When/where is it feasible to use a solar cooker to boil water?
Just a matter of money; you can boil all the water you want with enough focusing solar collectors . There is an installation ( maybe more) in AZ (?) that melts metal with this method. Reliable,good ,...
- 560
1
vote
How can I conserve energy and water in my bathroom?
To save water get a low flow shower head and when using the sink use the lowest flow rate of water. If possible, spend less time in the shower.
To use less water in the laundry, consider using the ...
- 3,517
1
vote
How can I conserve energy and water in my bathroom?
Stick a water meter on your shower and bath taps. This one looks adequate
I don't know what the optimal time to spend in the shower is, or whether a long hot deep bath is more satisfying than a long ...
- 1,230
1
vote
on demand water heater - propane vs electric?
This depends on the amount of CO2 generated by both sources. Propane (LPG) generates around 230g CO2 per kWh used (source https://www.volker-quaschning.de/datserv/CO2-spez/index_e.php ).
Divide this ...
- 11
1
vote
on demand water heater - propane vs electric?
Price
Looking at tankless water heaters on the website for Home Depot, a large home improvement product retailer in the US:
For gas water heaters (natural gas or propane) in the 4 to 4.5 gallon per ...
- 12k
1
vote
on demand water heater - propane vs electric?
The principal question about using electric heaters is, where does the electricity come from. If it must be generated from fossil energies more than 50% of initial input energy gets lost. This is the ...
- 929
1
vote
Feeding hotwater into modern appliances
The only appliances that take a water feed:
Washing machine. Most have both a hot and cold line connection. I've yet to see a single feed machine.
Dryer with steamer. Has hot water connection, ...
- 7,247
Only top scored, non community-wiki answers of a minimum length are eligible