Future Energy Needs and Consequences From a Physical

Sciences Perspective

The sun is the largest exploitable resource:

1 hour of sun to earth = all of mankind’s yearly energy:

Basic Science: How to capture and store?

Photosynthesis

Artificial photosyntesis

Uses of Solar Fuels

Hydrogen and carbon-based feedstocks are widely used in industry.

Fertilizers

Pharmaceuticals

Plastics

Synthetic fuels

Challenges in large-scale productionof solar fuels

Efficient, so that they harness as much of the sunlight hitting them as possible to produce fuels.

Durable, so that they can convert a lot of energy in their lifetime relative to the energy required to install them.

Cost effective, so that solar fuels are commercially viable.

All working together

Integrating the different processes and materials involved, from capturing and channeling sunlight through to producing a chemical fuel;

Identifying inexpensive catalysts to drive different aspects of the process

Developing ways to avoid the system degrading quickly because of exposure to sunlight.

Supercondutivity

TemperatureR

esi

stiv

ity Kelvin (1902)

Matthiessen (1864)

Dewar (1904)

H. Kamerlingh Onnes

“Mercury has passed into a new state, which on account of its extraordinary electrical properties may be called the superconducting state”

1911: Liquid Helium (B.P.: 4.2K)

1911: Observed that electrical resistance R(T)

of mercury vanished below Tc=4.2K

Tc Superconducting critical

temperature

1913: Nobel Prize in Physics

Discovery of Superconductivity

Origin of superconductivity

Metal:

• Periodic arrangement (lattice) of positively charged ions “Gas” of mobile negatively charged changed conduction electrons.

Normal State: Scattering of electrons by:

• Thermal motion of ions

• Impurities

• Other electrons

Superconducting state:

• Electrons with opposite momentum P and spin S are paired (P ,-P )

• Electron pairs move in concert through lattice

e-

e-

Phonon

Cooper pair model

Superconducting materials: Maximum Value of Tc versus time

1920 1940 1960 1980 20000

20

40

60

80

100

120

140

Cs2RbC

60

MgB2

LHe

Liquid nitrogen

HgBa2Ca

2Cu

3O8

Tl2Sr2Ca

2Cu

3O10

Bi2Sr2Ca

2Cu

3O10

YBa2Cu

3O7

La2-xSrxCuO

4

Ba1-xKxBiO

3

BaPb1-xBixO3

NaxWO

3NbO

Nb3Ge

Nb3SnNbN

NbPbHg

TC [

K]

Year

A superconductor is a perfect diamagnet. Superconducting material expels magnetic flux from the interior.

Superconducting Aplications

The grand challenge with superconductors

Superconductor state only happens at very low temperature

The mechanism for the materials are not well-known yet

Non-superconductor Nano-vortices within superconductors (quantum vortex)

Energy considerations

IPhone uses more energy than your refrigerator

More E to stream a video than to manufacture and ship a CD

10% of E consumption is on wireless

Waste is unavoidable

No foreseeable ceiling for use of E for devices

The Problem With the Actual Technology

The actual technology already has problems with its compounds that do lose energy in its operation.

Magnetoresistence

Electrical heating

Mechanical deformations by heating

New technologies

Plasma

Optical fiber (uses photons/computers uses electrons)

Excitons

Homemade Sun

The Tokamak Reactor

Is based in the principle of magnetic confined

Inside of it we have temperatures of about 150 million of Celsius degrees Forming a hot plasma

Has superconducting coils surrounded the tokamak

The issue here is how we can confine it

The conclusion

We actually have a big amount of technologies that would be a solution for our energy necessities, but actually need more research in this fields.

Talking about synthetic photosynthesis we need more research and start to use prototypes than allows improve this technology.

About superconductors we need to understand in a better way the physics of these things.

The nanomaterial actually are very used maybe we thing another ways for use this materials for avoid our energy wastes.