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MARY JO MEISNER: Good morning, everyone.
My name is Mary Jo Meisner, and I'm
Vice President for Communications and Public
Affairs at The Boston Foundation.
The Boston Foundation is pleased to be the leading
sponsor of this very important three-day conference on climate
change.
This is the first session of day three.
What we're going to do today is look forward
to the next century for this first session
and talk about adaptation and mitigation.
We have four excellent speakers lined up for you this morning.
We will allot time at the end of all of their presentations
for about a half hour of Q&A with all the speakers,
and I'll moderate that.
The speakers they can go ahead and have a few questions
and answers right at the end within their segment.
With that, I'd like to introduce our very first speaker
this morning, and that is Robert Armstrong.
Robert is the co-founder of the Massachusetts Institute
of Technology's Energy Initiative.
He is the Chevron Professor of Chemical Engineering at MIT
where he has been on the faculty since 1973
and has served as the head of the Department of Chemical
Engineering from 1996 to 2007.
He was elected into the National Academy of Engineering.
I believe that was in 1992, and he's
won several other awards for the work
that he has done in the fields of chemical engineering.
He is going to speak to us this morning
about technology pathways to reducing
carbon footprint of our energy system.
And with that, I'd like to Robert to come up.
PROFESSOR ARMSTRONG: Good morning.
Welcome to a nice warm day in Boston.
It's a pleasure to be here and have a chance
to talk to you about technology and climate change.
As you've heard-- can you hear me OK?
OK.
As you've heard in talks already in this symposium
you've learned a lot about the looming challenges
of climate change.
You've probably heard some and you will hear more
about policy solutions and way to address climate change
through policy.
What I'm going to talk about is what
do we do in the absence of policy.
I think you can't help but watch our system in the US
and notice that we're not jumping
very quickly on the policy solutions to climate change.
At least for the immediate future,
we are in a business-as-usual scenario.
And if you look at projections going forward after mid-century
and beyond, if we were to stay on a business-as-usual
scenario, then we're going to see significant increases
in energy consumption, significant increases in use
of fossil energy sources, roughly 80%
fossil energy sources out to mid-century and beyond,
and we'll see significant increases, of course,
in CO2 in the atmosphere and associated increases
in temperature.
I think the question that we look at
is what can we do in the meanwhile?
Do you do see progress in Washington.
The EPA's proposed emissions regulations on power plants
is certainly encouraging.
But in the absence of a price on carbon,
which will really help to reset the marketplace,
what can we do?
I think one of the great options we
have available to us is to take advantage of technology
and what we can do with new innovation, research
and development, and technology to address climate change
issues.
I am certainly not standing here telling you
this is the answer because I don't think that's so,
but I do think it's a strong contributor to the solution
in any scenario you imagine, and I
think it's a really important piece of the puzzle today given
the lack of a significant policy.
Let me talk about the technology options
that we can employ today.
Three principal routes we can take with technology today.
The first of those, the one in the top right here,
is building efficiency or efficiency more generally.
How can we get more use out of the energy we consume, get
better use of it so that we need reduce
the energy intensity of our system?
I'll give some examples there.
A second approach we can use is fuel switching,
take advantage of the fact that we
can move in some sectors, particularly power generation,
from high-carbon content fuels to lower carbon content fuels
and with the same production of electricity
have a smaller carbon footprint.
I'll talk specifically about switching from coal
to gas, which is certainly underway in the US in a big way
today.
And then lastly, I'd like to talk about research
and development to drive down the cost of low or zero carbon
energy solutions.
In the absence of a price on carbon,
you'd love to be able to get there just through technology
alone.
If I could develop the magic technology
and make a zero carbon energy system that's
cheaper than fossil energy systems,
then I would have a winner.
I doubt we'll get there.
But in any scenario, the lower we
can get the cost through technology the better
off we are.
Let me give you maybe a half a dozen little vignettes
of technology contributions in those three areas.
I'll start with the efficiency because I
think everyone agrees that this is
the low-hanging fruit out there.
There's a lot of disagreement over why we're not picking up
all this low-hanging fruit, but it is there,
and I think there's a lot of interesting technology
we can apply to taking advantage of efficiency options.
Here's an example of a way to take advantage of waste heat.
This may not be something you'd think about every day when
you get out, but it's a really important problem
in the industrial sector and the power sector in the US
and in other major economies around the world.
Much of the energy we produce comes
brings along with it what we call low-grade heat.
It's heat and energy, but it's at such a low temperature
that you can't do useful work with it.
So it's generally just thrown away.
It's exhausted into the air.
It's exchanged with water for cooling but otherwise lost.
A good question is can you take that waste heat
and use it as a source of important energy
for useful applications?
An instance you may all be familiar with there
is combining power plants with district heating.
If you take the waste heat that comes out
of a power plant and your close enough to residences
or businesses that need heating for space heating,
then you can use that waste heat from the power production
for that domestic heating.
Here's an example of using that waste heat
to improve the efficiency of battery storage.
Here you take advantage of the fact
that for rechargeable batteries the voltage
at which the battery works is different
depending on the temperature.
At high temperatures, you have lower voltage.
At low temperatures, you have higher voltage.
The idea here is to heat up a rechargeable battery in step 1.
That's this piece here.
Then when it's hot, you charge the battery at lower voltage.
You cool down the battery, and then
it will operate at higher voltage, and you discharge it.
You get more energy out of the battery
than you put in through the charging process.
Then you all get skeptical and say, "That can't be."
You don't get more energy out of the battery
than you put in, in total just through charging process.
The other energy comes from the heating step here,
but you're using waste heat, low-grade heat, that otherwise
you would throw away to the environment.
This is work it from a lab here at MIT,
Gang Chen in Mechanical Engineering,
and collaborators at Stanford University.
In the early experiments, they've done a 5% to 6%
increase in efficiency of the battery system,
and that could be very important for large-scale storage
applications.
The second example is how we warm buildings
to make occupants comfortable.
Generally, what we do is, of course, heat the entire space
in a building or-- well, certainly in New England we
mostly heat places.
I think on a day like today you this more about cooling.
This example is focused on heating.
There's a lot of space where there
are no occupants at a given time,
so you're wasting all the heat you put in.
Here's an idea that comes out of Carlo Ratti's Sensible City
Laboratory here at MIT where he takes advantage of the fact
that we all walk around with a lot of Wi-Fi broadcasting
equipment on us.
You can use that to track where occupants of a building
are and then use that signal to direct
ceiling-mounted infrared heating sources to warm people
where they are in the building, so you just warm locally
around your environment, so a little bit
like sitting outdoors at a restaurant in New England when
it's a little bit too early in the spring.
They have these little radiant heaters that they put over you.
That's a way to take advantage of the localized heating
capability, not wasting elsewhere in the building.
With more information from your cell phone,
you could actually tune the temperature
you like as an occupant, so you can adjust the comfort
level individually.
Third example of efficiency is fuel switching.
Here we want to take advantage of the fact
that not all fossil fuels are the same.
Some of them have a lot more carbon in them per unit
of energy than others.
In particular, coal has the highest carbon content.
Natural gas has the lowest.
Interestingly, both of those are used
in large quantities in the power sector.
What we're looking at here is the opportunity
to switch from coal to natural gas
and save on our carbon footprint.
To do that efficiently without a price on carbon,
you need to be able to take advantage
of existing infrastructure.
If this meant going and building a lot
of new natural gas-fired power plants,
it probably wouldn't be economical.
But it turns out that we have today because of over expansion
in the '90s, the US has as a large excess capacity
of natural gas combined-cycle power plants, so-called NGCC
plants.
You can see that in this top graph which
looks at-- in the blue bars, the darker bar--
the percentage of nameplate capacity
for production of energy and in the light blue bars
the percentage of actual output of energy
from these different power plants.
You could see that there's a little bit better
than 40% of the capacity for the power sector
is in natural gas power plants, but somewhere in the low 30s
is the actual output at least as of around 2010 to 2011,
actually at 23%.
Coal, on the other hand, has a lower capacity
in terms of base load capacity, but it's used more.
It's used as base load power capacity,
so there's actually more electricity produced
from coal in the US than by natural gas.
But you see from the blue bars there's the capacity sitting
on the ground to make electricity from natural gas
without building any new capacity.
It's just a matter of fuel switching.
In fact, we've seen that in the US
over the last couple of years driven simply
by the price difference in natural gas
as more shale gas comes online.
Two years ago, natural gas and coal-fired power
were almost at parity in the US.
This past winter because of the severe winter natural gas
prices spiked, and coal went up a little bit relative
to natural gas but not to these previous levels.
We're actually moving in the direction of lower carbon
emissions from our power sector simply because of price changes
in the fuel system.
Lastly, I'd like to look at low or zero carbon
technologies for producing energy.
I'll use solar as the prime example
here because I think we all agree
this solar is the big renewable resource we have.
The problems with solar are twofold.
One is how to make it cheap enough,
and the second is how to make it dispatchable,
so what do you do at nighttime fundamental?
This is an example of a the technology in solar called
concentrated solar power in which you take
incoming solar radiation and you use mirrors to focus it
on some receiver that gets really hot.
And then you use that hot receiver material, generally
a fluid that you heat up, you use
that to drive a power cycle much like you
would use in a coal-fired power plant
or in a natural gas power plant.
In this novel arrangement for concentrated solar power,
there's an arrangement of mirrors
that you can put either on a hillside or in a flat plane
which beams solar energy into a big tank which
is full of a molten salt.
You use something like a potassium sodium nitrate
mixture, which melts at very high temperatures,
so it melts around 220, 230 degrees centigrade.
You heat that up to 550 degrees centigrade or so,
which is near the upper limit of traditional steam power cycles.
You heat this bath of fluid up.
During the daytime, you can actually heat up excess fluid.
You can have what I draw as blue stuff at the bottom.
That's coal fluid.
Coal in this case is maybe 250 degrees Centigrade.
But then you heat it up with excess solar during the day
to 550 degrees or so.
Then when you need power, whether it's day or night,
you can pull out hot molten salt.
You can run that through a heat exchanger
to produce steam to drive a traditional steam power cycle.
And again, this is dispatchable because you
can use it day or night.
This overcomes a number of problems
with today's concentrated solar power technologies--
one being that you have built-in storage, two being
that with this molten salt you can
go to very high temperatures.
You can go well above 600, which limits the typical steam power
plant, and you can go to a much more efficient power cycle.
You can, for example, use what's called a Brayton cycle, which
uses a gas as the working fluid, which is what's driving you
when you're flying on a jet.
The jet engines use a Brayton cycle.
That get rid of water cooling problems, which
are a big issue with concentrated solar.
There are interesting solar technologies
on the horizon that promise higher efficiency and also
dispatchability.
The other big solar technology, of course, the biggest
solar technology today is photovoltaics.
There are lots of different innovations
underway with photovoltaics.
An example I'm going to show here
is photovoltaics technology looking
at the photovoltaic materials and the electrode material
how to design those with material science
to make them transparent.
If you can make them transparent,
then you can cover lots of surfaces
we have around cities, like the glass in the John Hancock
Tower, with PV material.
The occupants still get light in to light their work,
but you can make electricity from all of that surface area.
Just to give you an example of this technology,
you could also put this on your iPad or your cellphone
so that you could charge your iPod
or cellphone while you were working.
Is it working?
Ahh, here we go.
Here we go.
This movie illustrates the transparency
of the glass and the PV material.
You can see that when you cover up the surface
on this little cell phone that the voltage drops there.
In fact you are powering from the light
that this is receiving.
If you remove the glass cover, you
can see that in fact it is transparent.
We do have the technology to do this.
We need to make it more efficient to be sure.
And we need for building applications
like a big commercial building, John Hancock Tower,
you need better technology for connecting it
to the building's electrical system.
But I think there's a lot of promising technology there.
The other challenge here with PV in particular
is storage-- how are you going to store
the energy for nighttime use.
There's a lot of work in the battery space going on.
This is an example of a novel battery system
which uses two liquid electrode materials or two
liquid electrolytes which rather than being separated
by a membrane, which is typical in a battery like this,
they are separated simply by the flow patterns.
It's what's called a laminar flow, so they flow side by side
and don't interact over the distances
of the battery With this technology,
the researchers here at MIT, Martin Bazant and Cullen Buie,
have gotten to roughly three times the power
density of previous hydrogen bromine batteries,
and they've gotten to a much cheaper system
because they can eliminate a very expensive membrane.
Last example is storage for wind as another example for how
we might do storage with intermittent renewables.
One of the most attractive wind sources
is offshore wind because offshore wind velocities are
generally larger than on shore, and they're generally
more sustained, so it's a good place to put wind.
It's also interesting in that it's
easy to provide a storage solution with offshore wind
if it's far enough offshore so you
need to use a floating platform.
If you have a floating platform, then
you have some way to anchor, tether the platform
to the bottom of the ocean.
In this idea from Alex Slocum in Mechanical Engineering here,
he uses a series of large, hollow concrete spheres
or structures to serve as anchors.
The idea is that when I have excess wind
I use the power I don't need to transmit
to shore to pump water out of this big sphere.
When I don't have enough wind, I can let the water flow back
into this sphere and drive a turbine
as it flows back inside.
Essentially, I'm using the anchoring system
as a pumped hydro storage system.
It's much cheaper than trying to build a pumped hydro system
onshore.
I've give you a couple of brief examples of technology
solutions to moving towards reduction
of CO2 emissions in the energy space.
That's an example of game-changing technologies
for improving the environment.
These game-changing technologies in energy
can also have a big impact on the US
and other nations around the world in terms
of economic growth.
They provide jobs for people to build these new devices,
new industries, and I think it provides security
in that it provides people around the world
available energy that doesn't require the global transmission
systems or trade systems that we often need.
A message that I would like to leave you with
is that one of things I think we need in this country
is more and sustain R&D spending to keep
this pipeline of innovation in the energy space going.
Just yesterday we released a new book
called Game Changers-- Energy on the Move.
This is an unabashed plug for this book,
for which I get no royalties though.
This came out yesterday.
George Schultz at Stanford and us at MIT
had put this together to provide a set of examples
of how these game-changing technologies have already
made a difference and will likely
make a difference going forward.
So with that, I thank you for your attention
and leave you with this note that we can never
be too complacent.
I love Will Rogers' comment that "Even if you're
on the right track, you'll get run over
if you just sit there."
Thank you very much.
[APPLAUSE]
MARY JO MEISNER: We might have time for one question
before we start the next presentation.
Is there anyone that's got a question for Robert?
Right here.
AUDIENCE: I was hoping you could spend a couple minutes talking
about maybe Nocera's work for the photovoltaic
and would have nuclear fusion, like how far off would that be?
Is that a possible game-changing technology
that we'd see in the next decade or so?
PROFESSOR ARMSTRONG: I'll say a few words
about at least the first one.
MARY JO MEISNER: Robert, if you could
use the microphone, because it's been--
PROFESSOR ARMSTRONG: OK.
Let me say a few words about the first one.
We don't have a lot of time.
With solar storage, storage for solar energy,
there are two time scales you have to worry about.
One is day to night, and I think you
could do that with batteries and the ideas I've shown.
There's another storage time scale which is seasonal--
how do you get from summer to winter,
which in the Northern Hemisphere we're quite familiar with,
but obviously it's a problem in the Southern Hemisphere.
There's also the issue of how can solar
make a difference in the transportation market.
There you have to electrify it otherwise,
and battery storage for cars is a challenge.
There's some interesting ideas in the marketplace today.
I like the idea of using solar energy to produce hydrocarbon
fuels, renewably in the long-term future.
Dan Nocera's work-- which began here at MIT, now
is at the Harvard-- take solar energy
and uses it to catalytically split water into hydrogen
and oxygen.
Then you can recombine hydrogen and oxygen in a fuel cell
to produce electricity and water as a byproduct
and recycle that.
The energy input is sunlight, and you
make a fuel that can be used to make electricity on demand,
and you can store the fuel as long as you want.
The challenge there's it that hydrogen
isn't so easy to store, particularly
for transportation applications.
The best way known to man to store hydrogen
is to stick it on a carbon, and there's
a lot of interesting chemistry for doing that.
You can use solar energy, thermal energy
as well to do the reactions to put hydrogen on carbon
and at the same time reduce carbon dioxide to these higher
energy states.
I think personally that that's the technology in the future.
But it is well on in the future.
We're still in need of the right technologies there.
That's what I would call very early stage game changers work
but very important I think for the 15-, 20-year time horizon.