SECOND ASSIGNMENT
Hailey Mount
One article states that solar energy can be used to cool homes - how would that work?
From what I know about air conditioners, they use electricity like any other appliance. Since solar energy from PV panels is electricity solar energy could power A/C and cool homes. One article cites that, “One of the biggest benefits that rooftop solar provides to the grid is that it often produces electricity when—and where—that power is most valuable. For example, in many regions demand on the electricity system peaks in the afternoon on hot, sunny days, when air conditioning use is high and when rooftop solar is performing strongly. Such systems therefore help utilities meet peak demand without firing up seldom-used power plants that are both expensive and more polluting than most other options.” (
http://www.ucsusa.org/clean-energy/renewable-energy/how-solar-panels-work#.WI4lifkrLIV)
What happens to all the energy, in the form of sunlight, that falls on the earth that we don't capture with solar panels?
Most sunlight that travels to earth and is absorbed/ turned into heat. Plants also utilize energy from sunlight by using the stimulation of electrons from the light energy to change a chemical bond within themselves, in turn producing fuel. When it is absorbed by certain materials, however, energy from sunlight can create an electric current (solar power).
What's the light absorbing component of most solar cells?
Silicon crystals are used in most solar cells to absorb sunlight and convert it into electricity. Two semiconductors, one “p-type’ made with impurities of boron in the silicon crystal and one “n-type” with impurities of phosphorus, convert the energy into opposite charges to create a current.
Why is a solar panel also called a "photovoltaic" panel?
“Photovoltaic” refers to the creation of an electric current that comes from the exciting of electrons to carry the electric current. Solar panels create an electric current by using two oppositely charged semiconductors and exciting the electrons within the impure silicon crystals. “Photovoltaic panel” (PV) is just referring to the way in which the cell converts light to energy (electricity) as opposed to concentrated solar power (CSP) which uses the sun’s heat to produce energy.
Ben Rybisky
One article states that solar energy can be used to cool homes - how would that work?
The same way electricity is used to cool homes currently--through the use of air conditioning systems. The most efficient use of power, however, would be a heat pump system. It draws significantly less power than a conventional air conditioner, and is also reversible (to use for heating in the wintertime as well).
What happens to all the energy, in the form of sunlight, that falls on the earth that we don't capture with solar panels?
Some of that energy is used in photosynthesis by plants, some is converted into heat, and some is reflected back into space.
What's the light absorbing component of most solar cells?
Crystals. From the sound of the articles, the type of crystals change from panel to panel, and scientists working in labs use different types to try and raise the relative efficiency of panels. Currently, the crystals are mostly made of silicon and bonded to other chemicals to increase their efficiency.
Why is a solar panel also called a "photovoltaic" panel?
Photovoltaic = (Photo) + (voltaic) = electric light. "Photo" means light, "voltaic" is a reference to the fact that the energy produced by the panels is measured in volts.
-Spencer Knickerbocker-
One article states that solar energy can be used to cool homes - how would that work?
Solar energy can be used to cool homes because it can supply enough power to operate air conditioning on a hot day. Hot, sunny days are the most commons times for excess demand of electricity and these conditions are the most ideal for harnessing solar power.
What happens to all the energy, in the form of sunlight, that falls on the earth that we don't capture with solar panels?
All of the energy in the form of sunlight that falls on the earth turns into heat. A third of it is reflected back once it hits the atmosphere, and some of it is turned into energy by plants in the process of photosynthesis.
What's the light absorbing component of most solar cells?
The light absorbing component of most solar cells are silicon crystals. The silicon crystals, when “doped” with intentionally added impurities and hit with sunlight, an electric current is created. The bottom layer of the cell is doped with boron which creates a positive charge while the top layer is doped with phosphorous and creates a negative charge.
Why is a solar panel also called a "photovoltaic" panel?
Solar panels are called “photovoltaic” panels because the term describes what is happening in the panel. The process of photovoltaics is the conversion of light into electricity by using semiconducting materials which are, in this case, silicon crystals doped with boron and phosphorous.
Kenneth P. Callahan
26 January 2017
Solar Power at Marlboro
Solar Panel Reading Questions
Solar energy could be used to cool homes because the electricity generated by photovoltaic cells could be used for heating and cooling systems in a house. Cooling would be done in the summer, and heating in the winter.
A lot of the sun’s energy is reflected by the atmosphere and cloud layer way before it reaches the earth’s surface, and even then some of the light is reflected back into space. Only a small amount of radiant energy is absorbed by the earth's surface and felt as thermal energy.
The photovoltaic cell has layers of doped silicon crystals, meaning that intentional impurities are added to the silicon crystals in order to create positive and negative poles. The photons are absorbed by the silicon crystals and an electron moves into the excited state, able to freely flow around the substance. Since there is a negative and positive pole, the electrons are attracted to the positive pole but can only get there through a thin wire, creating an electric current.
Photovoltaic relates to the production of energy at the junction of two substances exposed to light. In the case of solar panels, they are composed of a positive pole, silicon doped with boron placed at the bottom, and a negative pole composed of silicon doped with phosphorous oriented at the top of the panel. These substances, exposed to light and with slight manipulation, creates electric current, thus giving them the name of photovoltaic panels.
- One article states that solar energy can be used to cool homes-how would that work?
The solar heater takes in solar energy and provides it to a substance such as silica gel, this causes evaporation and drying of the substance. The process can then be reversed, with the silica gel taking in heat and moisture from the air to be released outside of a building—thus cooling and dehumidifying the building.
- What happens to all the energy, in the form of sunlight, that falls on the earth that we don’t capture with solar panels?
Much of it is absorbed by plants through photosynthesis to produce sugars, some is reflected back into space, and the rest becomes heat.
- What’s the light absorbing component of most solar cells?
Silicon
- Why is a solar panel also called a “photovoltaic” panel?
“Photo” is light, and “Volt” is related to electricity, therefore a photovoltaic panel is a panel that converts light into electricity
Ryan Stampfli
Ryan Stampfli
Q1) One article states that solar energy can be used to cool homes - how would that work?
Solar power can cool homes by creating electricity to power air conditioning units. The process is more effective in warmer, drier environments. The heat of the local climate is also the driving factor for the high heating costs. This creates a correlating effect that when cooling bills are higher, the amount of energy available will also increase.
Q2) What happens to all the energy, in the form of sunlight, that falls on the earth that we don't capture with solar panels?
Light energy that falls to Earth and is not absorbed by solar panels is distributed in several ways. When light reaches the atmosphere, some is absorbed by aerosols in the air, and some is reflected into space. The energy that does hit the ground is absorbed into material. Light colored substances will reflect most of the light, while darker colored substances will absorb most light.
Q3) what's the light absorbing component of most solar cells?
The light absorbing component of most solar panels in the material used in the face of the panel. It is black to absorb the highest amount of light, and can vary in material from silicon to cadmium. Silicon is usually grown in large single crystals, which are then shaved into the required shape for the panel. Sometimes multiple crystals are used, however panels created using this method are less efficient. An alternative method is the spraying of material onto a panel. This method is cheaper but is also less efficient.
Q4) why is a solar panel also called a "photovoltaic" panel?
Solar panels are also called ‘Photovoltaic’ cells due to the nature of the reaction that occurs when light hits the panel. Instead of the material simply heating up and moving around due to entropy, the light puts energy into the electrons of the material used, and those electrons create
