periodic rise and fall of the water level of sea which are carried by the
action of sun and moon on water of the earth is called the tide.
Photo voltaic effect?
‘Photovoltaic effect’is defined as the
generation of an electromotive force as a result of absorption of ionizing
A fuel’ cell’isanelectrochemical device in which the chemical
energy of a conventional fuel is converted directly and efficiently into low
voltage, direct current electrical energy.
Non-renewable source of energy?
Non-renewable sources of energy will get exhausted eventually in
future. Example: Energy from fossil fuels.
Solar cooker is a device which cooks food without using any
conventional cooking fuel/energy like cow dung straw, wood, coal, gas kerosene
or electricity. It converts sunlight into heat energy and cooks the food.
Two Types of
1 Box type
2 Parabolic solar cooker
;Box Cookers Solar box cookers
(sometimes called solar ovens) are the most common and inexpensive type of
solar cookers . These box cookers have a very simple construction and they are
made of low cost materials. The outer box is often made of wood. The inner box
is made of insulating material, which is covered with clear glass or with
plastic, and often has a reflector of aluminum . According to Solar Cooker
International, solar box cookers cook at moderate temperatures and often can
accommodate multiple pots. It can reach a temperature of 140? C. The solar box
cooker, like other solar cookers, needs direct sunshine to operate and produces
zero emission;.Parabolic solar cooker
In comparison to
solar box and panel cookers, parabolic cookers (sometimes called curved
concentrator cookers) can reach much higher temperatures and can cook more
quickly, but require frequent adjustment and supervision for safe operation,
according to Solar Cooker International. It needs more precision to focus the
sunlight on the food in the pan. If the sunlight is not correctly focused on
the food in the pan, the food will not be cooked well. There are many designs
for parabolic solar cooking appliances. Because of the parabolic shapes and
with the aid of reflecting material quite a lot of solar energy is concentrated
in the focal point. A very high temperature of between 200 and 300ºC can be
reached because of a combination of the circular design, the size and the
polished aluminium. It is suitable for baking, roasting and grilling. Parabolic
solar cookers function well if they are used correctly. However, they are not
easy to make and need much care to use. Like other solar cookers, parabolic cookers
also need direct sunshine and they cannot store and keep sunlight for later
use.The Sun Strap is a flexible solar panel with a built-in
5.800 mAh battery and a 5V/1A USB output that can charge any USB device
such as your smartphone, tablet or camera.
With the Sun Strap, your bag becomes a charging station as
you go about your day but the Sun Strap is designed to be very light and
durable weighing only 5.8oz (165 grams).
The Sun Strap is capable of charging all your
mobile devices and you won’t have to worry about running out of battery when
you are away from outlets.
The Sun Strap has a large battery that
stores more than one charge of most mobile phones.
You can store up a reserve power on sunny days,
or charge the Sun Strap before leaving your home.
The Sun Strap is designed to fit any bag strap
and become a part of your bag in a stylish and comfortable way
The Sun Strap uses a flexible solar panel that goes around
any bag strap and charges its internal battery as you go about your day. Sun
Strap uses a 1.5W flexible solar panel and has a 5.800 mAh built in battery
that when fully charged is capable of charging an iPhone 5 3½ times. The Sun
Strap is made out of weather and water resistant fabrics.Renewable Resources—Renewable
energy resources are naturally replenishable, but flow-limited. They are
virtually inexhaustible in duration but limited in the amount of energy that is
available per unit of time. Some (such as geothermal and biomass) may be
stock-limited in that stocks are depleted by use, but on a time scale of
decades, or perhaps centuries, they can probably be replenished. Renewable
energy resources include: biomass, hydro, geothermal, solar and wind. In the future
they could also include the use of ocean thermal, wave, and tidal action
technologies. Utility renewable resource applications include bulk electricity
generation, on-site electricity generation, distributed electricity generation,
non-grid-connected generation, and demand reduction (energy efficiency)
facility for switching electric elements, transforming voltage, regulating
power, or metering.
The earth’s crust is heated by the decay of radioactive
elements. The heat is carried by magma or water beneath the earth’s surface.
Some of the heat reaches the surface and manifests itself in geysers and hot
springs throughout the world.
Geothermal power can be used to directly
heat buildings. Further, the pressurised steam from superheated water beneath
the earth’s surface can be used to power turbines and thus generate