I want to talk about an invention you likely
take for granted.
Your furnace.
If you live in an area that gets pretty cold
during the winter time, odds are you have
a gas-fired furnace heating your home.
Since you have gas lines in your house, you
likely cook with a gas-fired stove and oven,
and if you have a clothes dryer it is likely
also fueled with gas.
Even rural areas that don't have the infrastructure
to deliver natural gas via pipelines typically
will utilize gas fired furnaces that run on
propane, with businesses similar to Hank Hill’s
refilling the tanks of farm dwellers Nationwide.
Now you probably know that for every one of
these gas-fired inventions, there exists an
electric counterpart.
Electric furnaces are indeed a thing and can
be used to provide heat to the living space.
Electric stoves are very common.
And electric clothes dryers are very common
too.
In fact in areas that don't get that cold,
you'll often see most of these appliances
being largely Electric.
So then, why has the use of natural gas for
the furnace and other appliances remained
a staple of the midwestern home and elsewhere?
Well the answer is simple, and it has to do
with efficiency.
But as we’re about to see, this is going
to change.
For now, a furnace like this is designed to
burn a fuel such as natural gas and release
the heat of that fuel into the living space.
Furnaces are wonderful at doing this, even
the most basic gas-fired furnaces are 80%
efficient or more.
This means that they release at least 80%
of the heat energy contained in natural gas
into the living space.
In areas that remain cold for a long period
of the year, having an efficient furnace is
very very important.
Now, gas-fired furnaces are usually 80 to
90% efficient.
But electric heat is actually 100% efficient.
Sort of.
We’ll get back to that.
Electric heat is incredibly simple.
This is a $10 space heater that works just
fine.
It's able to be so cheap because all it is
is a coil of nichrome wire and a fan to blow
air past the wire.
The most expensive component in this space
heater is likely the fan motor.
Just as a point of comparison, this heater
puts out 5,120 btus, and the furnace for my
apartment delivers 45,000.
So less than 9 of these little guys could
replace the furnace, maybe even fewer since
furnaces are typically sized a little larger
than required to combat nastily cold days.
Of course space heaters are a terrible source
of permanent heat for many many reasons, most
important of which is safety, but nevertheless
it would work if there were enough separate
circuits throughout the apartment to power
them all together.
Electric heat is so simple because all you
need to do is run an electric current through
a resistive material, and that material will
heat up.
100% of the electrical energy you put through
that material will be released as heat.
This is the reason why electric heat is itself
100% efficient.
See when we talk about making electronic devices
more energy efficient, we are actually talking
about reducing wasted heat.
That's why modern LED lights bulbs are so
much more efficient than their Antiquated
incandescent counterpart--per unit of light,
they waste less energy as heat.
But when your goal is to create heat, you
can't get it any more efficient than 100%.
Sort of.
Hold on, I promise we’re getting somewhere.
A gas-fired furnace compared to a space heater
is incredibly complex.
It requires a sophisticated control system
to monitor and regulate gas flow as well as
ignite the flames upon startup.
It requires an expensive heat exchanger to
actually combust the gas safely and get the
exhaust from this process away from the living
space.
And it requires multiple fans and motors to
both expel exhaust and move air through the
furnace.
But putting up with all of this makes far
more sense in cold climates then using electric
heat.
See, although electric heat itself is 100%
Efficient, Electric power generation is nowhere
near that amount.
So long as we continue to use fossil fuels
to generate electricity, then using the fossil
fuel itself to heat makes far more sense.
A typical natural gas-fired electric power
plant will be about 40% efficient.
Subtract a few percentage points for transmission
losses (though in reality transmission losses
are very small across the electric grid),
and you're looking at a fuel to heat efficiency
of about 37% or so for an electric space heater.
This means that even the most basic gas-fired
furnace uses less than half the amount of
fuel to produce the same amount of heat.
And that means that gas heat is a lot cheaper
than electric heat, and it uses far less of
our precious natural resources.
And thus in cold climates, it makes far more
sense to have natural gas infrastructure capable
of delivering the gas itself to homes and
businesses then it does to rely solely on
electricity for heat.
A lot of natural gas would be wasted if it
was only used to generate electricity.
But this is almost certainly going to change.
Our electric grid is very soon going to become
100% renewable, or at least zero percent fossil-fuel
if nuclear power remains viable.
To be clear, very soon probably doesn't mean
in the next 10 years or so, but likely within
our lifetimes.
As solar and wind energy continues to get
cheaper and more ubiquitous, the electric
grid will become larger with less resources
required to fuel it.
Now of course we have energy storage and demand
problems to get sorted out, but I have faith
that with the Monstrous projects Humanity
has taken on in the past, we'll find a way
around it.
Once we have an electric grid capable of heating
everyone's homes with electricity, and it’s
able to do so at a cost that is less than
Natural Gas or propane, you should expect
to see electric stoves, electric dryers and
electric furnaces in every home.
This will come with so many advantages to
help make our lives more enjoyable.
For one thing, electric heat is so much more
reliable than gas-fired Heat.
One of the most reliable sources of electric
heat is the radiant baseboard heater.
These are still fairly common in older apartment
buildings, and you can buy them new for new
construction.
Electric baseboard heating does have the disadvantage
of taking up some visible space in every room,
but it is completely silent and lacks any
moving Parts whatsoever.
It is common to not have to replace these
for decades if at all.
Plus, if installed correctly, they offer a
comfort advantage as they create a flow of
warm air rising in front of windows and outside
walls, creating an air curtain that reduces
drafts.
But did you know there is actually an electric
heating solution that is not 100% efficient,
but up to 400% efficient?
Now before you start saying that breaks the
laws of thermodynamics, trust me, it doesn’t.
I'm talking about a heat pump.
Heat pumps are amazing things that have been
around for quite a while but are only just
now picking up steam.
A heat pump is essentially a modified air
conditioner that is able to operate in reverse.
See, air conditioners actually move three
to four times as much energy than they consume.
An 8000 BTU air conditioner and heat pump
might only use a quarter of the electricity
that an 8000 BTU resistive space heater would.
This means that even with a natural gas fired
power plant, a heat pump can move more heat
energy into a living space than the natural
gas itself contains, as 37% times 4 is 148
percent.
This is possible because the mechanical energy
of the compressor in an air conditioner is
used to move a refrigerant from a low pressure
state to a high pressure state, and it’s
the phase-change that occurs from gas to liquid
and back again inside a pair of heat exchangers
that actually absorbs and expels energy, moving
heat energy from one place to another across
a barrier.
I'm going to talk about this more in a later
video, but for now, know that the heat pump
is very likely going to become more and more
popular.
Right now they don't work so well in climates
like mine because when the temperature outside
drops below freezing, the efficiency of a
heat pump diminishes rapidly.
However, heat pumps are being combined with
geothermal heat sources which circulate a
heat transfer fluid underground to pick up
heat from Earth's crust.
These systems maintain a high efficiency level
even on the coldest of days.
While editing this video, I realized I needed
to clarify one thing about heat pumps.
The fact that their efficiency diminishes
below freezing isn’t the biggest problem.
Even in temperatures far below freezing, they
often can move more energy than they consume.
But along with getting less efficient, their
actual heat output also drops.
So even though a heat pump may be producing
twice the amount of heat energy for the living
space as it consumes, the fact is that it’s
now providing less heat.
So while a heat pump may provide 20,000 btus
of heat when it’s 45 degrees fahrenheit
outside, about 7 celsius, it might only produce
half that when it’s 20 degrees outside,
about minus 7.
Without a geothermal system in place to absorb
heat from, the heat pump must be supplemented
by a second type of heat.
Now I happen to know that PTACs, the air conditioning
and heater units commonly found in hotels,
are starting to also incorporate a heat pump.
This makes sense because a heat pump is really
just an air conditioner with a couple of reversing
valves added.
These newer units can tell when it’s too
cold outside for the heat pump to provide
enough heat, and will automatically switch
to using the resistive heater when necessary.
I think that this sort of logic might as well
be incorporated into a general heating and
cooling system, as in the spring and fall
months, even in a cold climate, there are
times that a heat pump could be effective.
If you’re installing an air conditioner,
you might as well spend the extra dollars
and make it a heat pump.
Anyway, back to the rest of the video.
To be clear, the gas-fired furnace is going
to stick around for a little while.
Until the point where electricity gets cheap
enough, and heat pumps become popular and
effective enough to provide cheaper heat than
a traditional furnace, well natural gas heat
still going to be popular.
But it is already the case that solar and
wind energy are cheaper than fossil fuels.
After all, once a solar panel is constructed,
it captures energy from the Sun and doesn't
need any sort of fuel to create electricity.
The Same goes for wind power.
Once a feasible storage solution is figured
out to deal with the intermittency problems
of wind and solar, nearly our whole world
will be powered with electricity.
And when that happens, well there will be
no need for gas lines anymore.
Thanks for watching this video on technology
connections.
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I'll see you next time.
