DC House Project (Direct Curent House)

DC House Solar Panel.
Renewable Energy.
a DC house is a house that operates solely on DC power from renewable and sustainable energy sources. The DC system is selected to provide optimum matching to renewable energy sources which mostly produce DC power. (Dr. Taufik)

1. DC-DC HOUSE
RENEWABLE ENERGY

2. Electric power
Electric power is the energy source is essential for human
life both for industrial activities, commercial activities as
well as in the daily life of the household. The electrical
energy needed to meet the needs of lighting and
production processes involving electronic goods and
equipment / machinery industries. Given the very large
and important benefits of electrical energy while the power
generation energy sources, especially those from non
renewable resource limited presence, in order to preserve
this energy source should be pursued strategic steps to
support the provision of electrical energy in an optimal and
affordable.

3. Electricity Customers Data
Realization during the years 2010-2014 the number of customers has increased
from 42.2 million to 57.2 million or an increase of an average of 3.5 million
annually. The customer additions still occur in the household sector, namely
an average of 3.2 million per year, followed by the business sector with an
average of 140 thousand customer per year, the public sector average of 82
thousand customers per year, and Last industrial sector average of 2 thousand
customers per year. Table indicates the growing amount of PLN customers
according to customer sectors in the last 5 years
Kementrian ESDM

4. Challenge
There are an estimated 1.4 billion people in the world today who do not have
access to electricity. This figure represents a significant issue in today’s world as
electricity is essential for economic growth, because it provides basic needs
such as lighting, refrigeration, and the operation of most household appliances.
Without these essential services, schools go unlit, some medicines cannot be
stored, and water must often be hand-carried for miles just to supply adequate
hydration and sanitation.
The Central Statistics Agency (BPS) recorded around 15.4 percent or more than
12 thousand villages and villages in Indonesia is not powered until the end of
2014, or 15.40 percent. Nevertheless, the number decreased compared to
2011, which reached 14 676 villages. Related street lighting, as many as 31 387
village main street low lighting. This figure decreased 41.77 percent compared
with 2011, as many as 32 834 positions villages.
Another alternative is needed to improve electricity supply to areas of non-
electricity.

5. DC House
As previously mentioned, a DC house is
a house that operates solely on DC
power from renewable and sustainable
energy sources. The DC system is
selected to provide optimum matching to
renewable energy sources which mostly
produce DC power.
This in turn eliminates the intermediate
conversion process which will otherwise
be required in traditional AC-powered
homes. That Figure illustrates the block
diagram of the DC House system.
Unfortunately, because the reliability of
many renewable energy sources is
subject to season, weather, or time of
day, it will be necessary to incorporate a
battery system to provide stability.
Dr. Taufik ; The DC House Project

6. DC vs. AC
Direct Current
•“Battery power”
• Electronics use
•Requires prohibitively
high voltage to transmit
over long distance
Alternating Current
•EASY to generate
•Can be transformed in
voltage
•Can be limited while
keeping voltage high
•Can be transmitted over
long distance without
super-high voltage
www.need.org

7. Direct Current
Direct current (DC) is a flow of electrical charge carriers that always takes
place in the same direction. The current need not always have the same
magnitude, but if it is to be defined as dc, the direction of the charge carrier flow
must never reverse. This contrasts with alternating current which varies the
direction of flow.

8. The Advantages of DC Power
The main advantages of DC power transmission in relation to the above
mentioned projects are:
1.reduction of energy losses;
2.a relatively simple integration of renewable energy sources such as PV
systems;
3.a simple coupling with storage systems;
4.better utilisation of the current electricity infrastructure, because of
higher power densities.
An example of a low-voltage DC supply in a Western European domestic
dwelling is the ‘Solarhome Castricum’, where a PV supplied 24 V DC
system supplies most of the household appliances. DC power supply
systems are also applied in Solar Home Systems, which are small PV
powered systems used for rural electrification in developing countries.
J. PELLIS : THE DC LOW-VOLTAGE HOUSE

9. DC House Project
www.need.org

10. Components of an autonomous DC house
PV Converter Charge Controller Battery DC low-voltage
grid
Household
Appliances
Function Conversion of
solar energy to
electrical energy
Control of energy
flow to and from
battery
Storage of
electrical energy
DC power
transmission from
supply to the user
Conversion of DC
power to heat,
rotation, noise,
light
DC/AC DC DC DC DC
12/24 V
DC
Loses 85% 20% -% -%
J. PELLIS : THE DC LOW-VOLTAGE HOUSE
PV Converter Charge
Controller
Battery DC/AC
Converter
AC grid Household
Appliances
Function Conversion of
solar energy to
electrical
energy
Control of
energy flow to
and from
battery
Storage of
electrical
energy
Conversion
from DC to AC
AC power
transmission
from supply to
the user
Conversion of DC
power to heat,
rotation, noise, light
DC/AC DC DC DC AC AC
220 V
AC DCAC/D
C
Loses 85% 20% 8% -% -% -% -%

11. Components of an autonomous DC house.
show that a reduction in the overall energy losses is possible by
avoiding conversion losses. The AC/DC conversion inside a
household appliance is necessary if this device operates internally
on DC, which is the case in many appliances. Three different
kinds of supply in the interior of the AC appliance can be
distinguished.
1. only DC power supply (for example, a computer or a radio);
2. DC and AC power supply (for example, a television or a
washing machine);
3. only AC power supply (for example, an incandescent lamp or a
heater
J. PELLIS : THE DC LOW-VOLTAGE HOUSE

12. DC Household appliances
Suitability for supply with DC and low voltage
Household appliances divided according to the type of energy conversion
J. PELLIS : THE DC LOW-VOLTAGE HOUSE
Kind of energy
conversion
Examples: AC supply
AC => DC
Converter
DC Supply Power
demand
(W)
DC => AC
converter
DC=>DC
Converter
electric energy -> heatboiler, coffee maker
light bulb, electric
cooker
No No No < 3500
electric energy ->
rotational or mechanical
energy
washing machine,
ventilator, vacum
cleaner
No < 3500
electric energy-> sound
and vision
TV, radio, CD player,
telephone
Yes No <500
electric energy -> light fluorescentlamp, PL No* Yes No <500

13. DC distribution a renewed interest
Nowadays AC distribution systems
are usually used for the supply of
electrical energy.
Although electricity transport by
means of AC is most widely used,
DC distribution systems still exist or
have existed for a long time, for
example, on boats, for railway
applications or for traction.
Nowadays there is even a renewed
interest for DC power transmission,
for, among others, the following
reasons:
 new developments in the area of
power electronics
 utilisation of renewable energy
sources such as DC generating solar
cells.
J. PELLIS : THE DC LOW-VOLTAGE HOUSE

14. Photovoltaics
www.need.org

15. www.need.org

16. How Solar Energy Works?
Photoelectric Cells: This method converts
the sun’s energy into electricity.
Photovoltaic cells are most popular form of
converting solar energy into electricity.
These cells are silicon based pieces of
materials that absorb the sun’s light. When
the sunlight enters the cells, it causes the
electrons to move. These electrons move in
a certain direction which is known as
current. This electricity is in the form of
direct current. The electrical output from a
single cell is small, therefore individual solar
cells are arranged together in a PV module
and the modules are grouped together to
form an array. This power is then used to
charge cells or inverters and this electricity
can be used to provide sufficient power for
common electrical appliances.
http://www.conserve-energy-future.com/Disadvantages_SolarEnergy.php

17. PV Array Fields
www.need.org

18. Source: Solarbuzz, a part of The NPD Group
www.need.org

19. PV systems
PV systems are solar energy conversion
systems, which either supply electrical
power directly to electrical equipment or
feed energy into the public electricity grid.
The power range extends from tens of W to
several M
PV systems can be divided in two main
categories:
1. grid-independent and
2. grid-connected.
Larger grid-independent or remote solar
power supplies are also called stand-alone
or autonomous systems. A typical example
of the second category is a system with
solar modules installed on house roofs,
which is connected to the public electricity
grid via a suitable converter
J. PELLIS : THE DC LOW-VOLTAGE HOUSE

20. PV Technology Classification
Prashun Gorai , Rahul Vyas , Saurabh Mathur, Akshat Gupta : Solar Photovoltaics

Silicon Crystalline Technology Thin Film Technology
Mono Crystalline PV Cells Amorphous Silicon PV Cells


Multi Crystalline PV Cells Poly Crystalline PV Cells
( Non-Silicon based)

21. Silicon Crystalline Technology
Currently makes up 86% of PV market
 Very stable with module efficiencies 10-16%
Mono crystalline PV Cells
•Made using saw-cut from single
cylindrical crystal of Si
•Operating efficiency up to 15%
Multi Crystalline PV Cells
•Caste from ingot of melted
and recrystallised silicon
•Cell efficiency ~12%
•Accounts for 90% of
crystalline Si market
Prashun Gorai , Rahul Vyas , Saurabh Mathur, Akshat Gupta : Solar Photovoltaics

22. Thin Film Technology
Silicon deposited in a continuous on a base material such as glass,
metal or polymers
Thin-film crystalline solar cell consists of layers about 10μm thick
compared with 200-300μm layers for crystalline silicon cells

PROS
• Low cost substrate and
fabrication process
CONS
• Not very stable
Prashun Gorai , Rahul Vyas , Saurabh Mathur, Akshat Gupta : Solar Photovoltaics

23. Amorphous Silicon PV Cells
 The most advanced of thin film technologies
 Operating efficiency ~6%
 Makes up about 13% of PV market
PROS
• Mature manufacturing
technologies available
CONS
• Initial 20-40% loss in
efficiency
Prashun Gorai , Rahul Vyas , Saurabh Mathur, Akshat Gupta : Solar Photovoltaics

24. Poly Crystalline PV Cells
Copper Indium Diselinide
 CIS with band gap 1eV, high
absorption coefficient 10
5
cm
-1

High efficiency levels
PROS
• 18% laboratory efficiency
• >11% module efficiency
CONS
• Immature manufacturing
process
• Slow vacuum process
Non – Silicon Based Technology
Prashun Gorai , Rahul Vyas , Saurabh Mathur, Akshat Gupta : Solar Photovoltaics

25. Poly Crystalline PV Cells
Cadmium Telluride ( CdTe)
•Unlike most other II/IV material CdTe
exhibits direct band gap of 1.4eV and
high absorption coefficient
PROS
• 16% laboratory efficiency
•6-9% module efficiency
CONS
•Immature manufacturing process
Non – Silicon Based Technology
Prashun Gorai , Rahul Vyas , Saurabh Mathur, Akshat Gupta : Solar Photovoltaics

26. Advantages of Solar Energy
http://www.conserve-energy-future.com/advantages_solarenergy.php
There are many advantages that solar energy has to offer over traditional
sources of energy like coal and oil. Not only it is completely renewable but is also
protects the environment. Here are some of the advantages of solar energy.
1.Non-polluting: Solar energy is an alternative for fossil fuels as it is non-
polluting, clean, reliable and renewable source of energy.
2.Renewable Source: Solar energy is a renewable source of energy as it can be
used to produce electricity as long as the sun exists. Sunlight is available
everywhere on the Earth.
3.Low maintenance: Solar cells generally doesn’t require much maintenance
and run for a long time. More solar panels can be added from time to time when
needed.
4.Easy Installation: Solar panels are easy to install and does not require any
wires, cords or power sources.
5.Can Be Used in Remote Locations: Solar energy can be of great boon in
areas which have no access to power cables.

27. The Concept of DC-DC Converter
Various types of RE, such as solar power (photovoltaic), wind generators, and
biogas, require inverters and converters so the user can be implemented to the
electrical load (such as televisions, monitors, computers, lights, etc.). But in fact,
some of the electrical load as mentioned earlier is the concept of direct current.
Peng-konversian necessary, from direct current to alternating current so that the
load can work. Therefore, converterless (in this case the inverter and rectifier),
can be used as a solution in order to increase efficiency and cost used can be
reduced.
There are several types of DC-DC converters are between the other Buck DC-
DC converters, DC-DC boost converter and DC-DC buck-boost.

28. The Concept of DC-DC Converter
Buck Converter: In Figure 2a a buck converter is
shown. The buck converter is step down converter
and produces a lower average output voltage than
the dc input voltage.
NPTEL – Electrical Engineering ; Module 4: DC-DC Converters

29. The Concept of DC-DC Converter
Boost converter: In Figure 2b
a boost converter is shown.
The output voltage is always
greater than the input
voltage.
Buck-Boost converter: In
Figure 2c a buck-boost
converter is shown. The
output voltage can be either
higher or lower than the input
voltage.
NPTEL – Electrical Engineering ; Module 4: DC-DC Converters

30. Protection of DC-based Systems
Basically, DC-based system is not different from the conventional
protection at the AC system.
1.Network fault can be caused by many things, one of which is because
there is an element of accidental connection between the elektroikal to
body or metal. The short-circuit could cause a fire or damage to the tool.
Therefore, the short circuit must be protected.
2.protection used is a fuse or use the MCB to the type of curve Z or B.
Where this class can detect short-circuit current is small. MCB
characteristic curve at an image can be seen in Fig. On the curve shows
that the curve Z and B have the characteristics of a smaller value of the
over current protection setting curves than other types.
J. Park and S. Member, “Ground Fault Detection and Location for Ungrounded DC T
raction Power Systems,” vol. 64, no. 12, pp. 5667–5676, 2015.

31. Protection characteristic curve
J. Park and S. Member, “Ground Fault Detection and Location for Ungrounded DC T
raction Power Systems,” vol. 64, no. 12, pp. 5667–5676, 2015.