The Canada-US trade and energy relationship - Policy Options
The Clean Energy Dialogue embarked upon by Canada and the United States testifies to this importance. On the one hand, because of the. Canada. A Canada Centre for Remote Sensing Remote Sensing Tutorial . Wavelength and frequency are related by the following formula: Therefore . Rayleigh scattering causes shorter wavelengths of energy to be scattered much atmospheric windows available to us, we can define those wavelengths that we can. This energy is in the form of electromagnetic radiation. Wavelength and frequency are related by the following formula: hear progressively lower sounds or frequencies (shorter wavelengths) until it reaches us, the original.
This abundance of hydropower means that Canada depends much less on coal-fired power plants for electricity than many countries do " the US included. The US derives significantly more electricity from coal than Canada does. The US also uses more natural gas for electricity generation. However, this abundance of hydropower does not necessarily translate into an advantage across all regions in Canada. In Ontario, for example, the provincial government maintains that it will close its four coal-fired plants Atikokan, Lambton, Nonticoke and Thunder Bay by December 31,citing environ- mental and health concerns.
The government plans to replace coal- fired capacity with natural gas, nuclear, hydroelectricity, and wind, along with increased conservation measures. These differences have obvious implications for any clean energy strategy.
On the one hand, the US can achieve very large emissions reductions by replacing its coal-fired electricity plants with less carbon-intensive alter- natives, while Canada requires a broader range of measures across multiple sectors to reduce emissions. On the other hand, electrification in Canada provides greater emissions reductions due to the lower emissions intensity of electricity generation.
This has implica- tions for both the ambition and pace of climate policy development and implementation here in Canada. Already, GHG emissions targets in Canada have been moderated to line up with less stringent proposed US targets, at 17 percent below levels by Yet US ambition and timing on the climate file remains unclear and uncertain.
Early momentum in Congress with the Waxman-Markey Bill, together with various Senate bills, has stalled. A federally mandated cap- and-trade system that could link with Canada remains in limbo. Clean ener- gy technology discussions have not yielded specific results. Recent tailpipe emission standards harmonization is the sole substantive element. An inevitable question for Canada will be whether and how it does some- thing on climate policy while the US does nothing and delays persist south of the border.
National Round Table on the Environment and the Economy NRTEE reports in and demonstrate that an early, economy- wide carbon price signal is the most cost effective means of meeting deep GHG emissions reduction targets. Delay is costly as the carbon price will have to rise to meet stated targets in a shorter time frame. Like all countries, Canada will seek to implement policies that achieve the most GHG emissions reduc- tions at the least economic cost. A core issue for the development of a clean energy strategy for Canada will there- fore be whether it takes action on cli- mate policy objectives now, or only at a later date pending US action.
- Electromagnetic Spectrum - Wavelength, Frequency, And Energy, Wavelength Regions
- Electromagnetic spectrum
For Canada, there are both risks and opportunities in US climate pol- icy and its impact on Canadian ener- gy and climate policies. Table 2, developed by the NRTEE, illustrates the types of trade-off risks at play from both an economic and environ- mental perspective in contemplating various leading, lagging, or harmo- nizing scenarios for Canada.
They include competitive sectoral impacts, regional distribution impacts, appli- cation of border carbon adjustments, and missing both medium-term and longer-term tar- gets. It offers a way to contemplate optimal Canadian policy design to minimize risks.
No option is risk-free " including harmonization " and there are inescapable costs to all options. The table is illustrative only at this stage; Canadian policy choic- es and responses will ultimately determine the likely level of risk. A core reason for these underlying risks is the dif- ferent expected rates of growth in GHG emissions in the two countries. This is reflected in figure 5, which shows the percent increase in GHG emissions over levels as predicted by cur- rent business-as-usual projections for Canada and the US.
According to Planck's law, the energy of the incident photons is inversely proportional to their wavelength. Short-wavelength radiation occupies the violet end of the spectrum and includes ultraviolet radiation and gamma rays. On the other hand, long-wavelength radiation occupies the red end and includes infrared radiation, microwaves and radio waves. Sunlight contains an entire spectrum of radiation, but only light with a short enough wavelength will produce the photoelectric or photovoltaic effects.
This means that a part of the solar spectrum is useful for generating electricity. It doesn't matter how bright or dim the light is. It just has to have — at a minimum — the solar cell wavelength. High-energy ultraviolet radiation can penetrate clouds, which means that solar cells should function on cloudy days — and they do.
Work Function and Band Gap A photon must have a minimum energy value to excite electrons enough to knock them from their orbitals and allow them to move freely. In a conducting material, this minimum energy is called the work function, and it's different for every conducting material.
Electromagnetic spectrum - Wikipedia
The kinetic energy of an electron released by collision with a photon is equal to the energy of the photon minus the work function. In a photovoltaic cell, two different semiconducting materials are fused to create what physicists call a PN-junction. In practice, it's common to use a single material, such as silicon, and to dope it with different chemicals to create this junction.
For example, doping silicon with antimony creates an N-type semiconductor, and doping with boron makes a P-type semiconductor.
Electrons knocked out of their orbits collect near the PN-junction and increase the voltage across it. The threshold energy to knock an electron out of its orbit and into the conduction band is known as the band gap.
It's similar to the work function. This is different for different materials.
Rearranging Plank's equation and solving for wavelength tells you the wavelength of light that corresponds to this energy: Any radiation with a longer wavelength, such as microwaves and radio waves, lacks the energy to produce electricity from a solar cell. Any photon with a energy greater than 1. In practice, however, very short wavelength photons with an energy of more than about 3 eV send electrons clear out of the conduction band and render them unavailable to do work.
The upper wavelength threshold to get useful work from the photoelectric effect in solar panels depends on the structure of the solar cell, the materials used in its construction and the circuit characteristics. Solar Energy Wavelength and Cell Efficiency In short, PV cells are sensitive to light from the entire spectrum as long as the wavelength is above the band gap of the material used for the cell, but extremely short wavelength light is wasted.