Napelem vlogats

1
Napelem válogatás

• Történelem
• Alapok
• Részletek
• Újdonságok

2
Use of energy today

• Oil is the most used energy source
• Natural gas is also used a lot
• Coal and charcoal are also used a lot
• Renewable energy is not used very much

3
Timeline of Photovoltaics

• 1839Photovoltaic effect discovered by Becquerel
• 1954First practical solar cell invented at Bell
  Labs by Chapin, Fuller, and Pearson
• 1960s and 70sSolar cell research focused on
  spaceflight applications
• 1973Oil embargo, energy crisis
• 1976Creation of the DOE, and its Photovoltaics
  Program

4
(No Transcript)
5
(No Transcript)
6
p/njunction with irradiationcrystal view
7
The real Silicon Solar-cell
8
Equivalent circuit of a solar cell
IPH photocurrent of the solar-cell
ID /UD current and voltage of the internal p-n
diode
RP shunt resistor due to inhomogeneity of the
surface and loss-current at the solar-cell edges
RS serial resistor due to resistance of the
silicon-bulk and contact material
ISG/USG Solar-cell current and voltage
RL/IL/UL Load-Resistance, current and
voltage ISG IL, USG UL
9
Solar-Cell characteristics
simplified circuit
10
Solar-cell characteristics
11
(No Transcript)
12
(No Transcript)
13
Timeline of Photovoltaics
Lewis, et al. Basic Research Needs for Solar
Energy Utilization.
14
Background and Cost

• Photovoltaics convert
• sunlight directly to
• electric power
• Carbon-neutral
• Highly abundantthe
• earth receives 120
• quadrillion watts of power
• from the sun, humans
• currently use about 13 trillion watts
• Costs
• Module cost
• Balance of system cost
• Power conditioning cost
• Currently about 0.30/kWh, a factor of 5-10
  behind total cost of fossil fuel generation

Lewis, et al. Basic Research Needs for Solar
Energy Utilization.
15
(No Transcript)
16
(No Transcript)
17
(No Transcript)
18
(No Transcript)
19
(No Transcript)
20
(No Transcript)
21
(No Transcript)
22
(No Transcript)
23
(No Transcript)
24
(No Transcript)
25
Timeline of Photovoltaics
Lewis, et al. Basic Research Needs for Solar
Energy Utilization.
26
Production process
1. Silicon Wafer-technology (mono- or
multi-crystalline)
Most purely silicon99.999999999
melting / crystallization
Occurence Siliconoxide (SiO2) sand
Tile-production
Mechanical cutting Thickness about 300µm Minimum
Thickness about 100µm
Plate-production
typical Wafer-size 10 x 10 cm2 Link to
Producers of Silicon Wafers
cleaning
Quality-control
Wafer
27
Production- Processmono- or multi-crystalline
Siliconcrystal growth process
28
Production - Process
Silicon Band-Growth Process
EFG Edge-defined Film-fed Growth Less
energy-consumptively than crystal-growth
process Thickness about 100µm Only few Silicon
waste, since no cutting necessary
29
Production Process
Thin-Film-Process (CIS, CdTe, aSi, ... )
semiconductor materials are evaporated on large
areas Thickness about 1µm Flexible devices
possible less energy-consumptive than
c-Silicon-process only few raw material
needed Typical production sizes1 x 1 m2
CIS Module
30
Technology -Trends

• Thin-Film Technology
• few raw material needed
• demand of flexible devices
• production of large area cells / modules in one
  step
• enhancement of cell efficiency
• Tandem-cell for better utilization of the solar
  spektrum
• Light Trapping, enhancement of the light
  absorption
• Transparent contacts
• bifacial cells
• Solar-concentrating photovoltaics

31
Tandem-cell
Pattern of a multi-spectral cell on the basis of
the Chalkopyrite Cu(In,Ga)(S,Se)2
32
Thin Si-Wafer
33
energy payback time (EPBT)
34
Market Shares
35
Solar-Cell Manufacturer
36
Worldwide installed PV-Power
37
In Germany installed PV-Power
38
PV-Module priceexperience curve price per Wp
against cumulative production
with Research Development
without Research Development
cumulative production in MWp
39
3. PV Systems and Components

• PV System-Technology
• Solar Irradiation
• Energy yield and savings

40
Solar Irradiation worlwide(kWh/m² a) on
horizontal surface
41
Example BP Showcase