Solar energy in the United States is booming. Below you will find charts and information summarizing the state of solar in the U. If you're looking for more data, explore our resources page. In addition, SEIA Members have access to presentation slide decks that contain this data and much more.
Join today! Thanks to strong federal policies like the solar Investment Tax Credit, rapidly declining costs, and increasing demand across the private and public sector for clean electricity, there are now more than gigawatts GW of solar capacity installed nationwide, enough to power As of , more than , Americans work in solar at more than 10, companies in every U.
Over the last 6 — 9 months, shipping constraints and other supply chain challenges stemming from the global pandemic are leading to price increases across the U. For the first time since Wood Mackenzie began modeling solar system price data in , costs increased in Q2 across all market segments both year-over-year and quarter-over-quarter. The Ecology of Carrion Decomposition.
Causes and Consequences of Biodiversity Declines. Earth's Ferrous Wheel. Alternative Stable States. Recharge Variability in Semi-Arid Climates. Secondary Production. Food Web: Concept and Applications. Terrestrial Primary Production: Fuel for Life. Energy Economics in Ecosystems By: J. Citation: Beman, J. Nature Education Knowledge 3 10 What powers life? In most ecosystems, sunlight is absorbed and converted into usable forms of energy via photosynthesis.
These usable forms of energy are carbon-based. Aa Aa Aa. Energy Production. In most ecosystems, the ultimate source of all energy is the sun. Plants and microorganisms on land and in the sea use photosynthesis to produce biomass living material : they absorb specific wavelengths of sunlight using the pigment chlorophyll, to convert sunlight to chemical energy, and "fix" i.
Many other organisms — humans included — consume these sugars, lipids, and proteins and use the stored energy to power their activities. In fact, the energy that powers our lights and fuels our cars is also "fossilized sunlight" — it is derived from organic material that has been buried at the bottom of the ocean or a swamp, and converted by heat and pressure to oil, coal, or natural gas over geologic time.
This leads to the often startling conclusion that the vast majority of the energy used on Earth ultimately comes from sunlight. There are three important exceptions to this, one that is significant in ecosystems, and two that have little influence in ecology. Both geothermal heat and nuclear energy have been harnessed by humans, but are not used by other organisms; these may be important energy sources in our cities, but not in natural ecosystems. In contrast, many microorganisms can generate energy by performing chemical reactions that convert compounds to different chemical forms, and release energy in the process.
These are known as oxidation-reduction or redox reactions. Some of these microbes can use chemical energy to fix CO 2 — just like photosynthetic organisms, but using chemical redox reactions rather than sunlight. This is not an important process at the global scale, but it can be very important in certain circumstances.
For example, nitrification is an essential biogeochemical process that is carried out by these "chemoautotrophs" globally. Among the best known examples are the remarkable ecosystems that flourish at deep-sea vents. Vent communities are not supported by the heat coming out of these vents, but are instead sustained by the chemical compounds e.
This chemical energy is the major source of energy supporting these ecosystems in their entirety, and before photosynthesis evolved, all of life on Earth was sustained in similar ways by the use of chemical energy. Energy Consumption. The sugars, lipids, and proteins generated by plants and microbes store energy from the sun in Carbon-Hydrogen C-H bonds; these are broken down in cells to release energy via respiration, and we also break them down from our fuel tanks to release energy via combustion.
Although respiration and combustion are very different processes, they ultimately produce the same result, which is to use oxygen to convert organic compounds containing C-H bonds back into CO 2. This process is highly energetically favorable, and so the organisms that use C-H bonds for energy range from tiny bacteria to large animals and nearly everything in between.
Some organisms use the energy produced by plants directly, some eat organisms that ate plants, some eat organisms that ate organisms that ate plants, and so on; some organisms use a mixture of carbon sources and some use waste products, but ultimately food webs lead back to the energy produced by plants and microbes.
This leads to several key insights. First, CO 2 that is fixed by photoautotrophs is eventually returned to the atmosphere; this may not be exactly equal — particularly as a result of human modification of ecosystems, and also over geological time scales — but it is usually close to equal. Renewable Energy. At-a-glance Renewable energy is the fastest-growing energy source in the United States, increasing 42 percent from to up 90 percent from to Renewables made up nearly 20 percent of utility-scale U.
Solar generation including distributed , which made up 3. Globally, renewables made up 29 percent of electricity generation in , much of it from hydropower A record amount of over GW of renewable power capacity was added globally during Renewable ethanol and biodiesel transportation fuels made up more than 17 percent of total U. Renewable Supply and Demand Renewable energy is the fastest-growing energy source globally and in the United States.
Globally: About Renewables made up 29 percent of global electricity generation by the end of Led by wind power and solar PV, more than GW of capacity was added in , an increase of nearly 10 percent in total installed renewable power capacity. In the United States: Almost 5 percent of the energy consumed across sectors in the United States was from renewable sources in Renewables made up Most of the increase is expected to come from wind and solar.
Non-hydro renewables have increased their share of electric power generation from less than 1 percent in to over Renewable Energy Drivers Factors affecting renewable energy deployment include market conditions e. Global weighted average levelized cost of electricity from utility-scale power generation technologies, and Policy Drivers Two federal tax credits have encouraged renewable energy in the United States: The production tax credit PTC , first enacted in and subsequently amended, was a corporate tax credit available to a wide range of renewable technologies including wind, landfill gas, geothermal, and small hydroelectric.
For eligible technologies, the utility received a 2. The PTC is currently being phased out; at the end of December , the PTC was extended for another year at 60 percent of the full credit amount, and facilities beginning construction after December 31, will no longer be able to claim this credit. The investment tax credit ITC is earned when qualifying equipment, including solar hot water, photovoltaics, and small wind turbines, are placed into service.
The credit reduces installation costs and shortens the payback time of these technologies. It will phase down to 10 percent in from 26 percent in Types of Renewable Energy Renewable energy comes from sources that can be regenerated or naturally replenished.
The main sources are: Water hydropower and hydrokinetic Wind Solar power and hot water Biomass biofuel and biopower Geothermal power and heating All sources of renewable energy are used to generate electric power. Water Large conventional hydropower projects currently provide the majority of renewable electric power generation worldwide.
Other Hydroelectric Power Generation Small hydropower projects, generally less than 10 megawatts MW , and micro-hydropower less than 1 MW are less costly to develop and have a lower environmental impact than large conventional hydropower projects. Hydroelectric Power Generation. Source Environment Canada, Wind Wind was the second largest renewable energy source worldwide after hydropower for power generation. Source GE, Vox, Solar Solar energy resources are massive and widespread, and they can be harnessed anywhere that receives sunlight.
Solar energy can be captured for electricity production using: A solar or photovoltaic cell, which converts sunlight into electricity using the photoelectric effect. Typically, photovoltaics are found on the roofs of residential and commercial buildings. Additionally, utilities have constructed large greater than MW photovoltaic facilities that require anywhere from 5 to 13 acres per MW , depending on the technologies used.
In the United States, non-residential solar e. Concentrating solar power CSP , which uses lenses or mirrors to concentrate sunlight into a narrow beam that heats a fluid, producing steam to drive a turbine that generates electricity. Concentrating solar power projects are larger-scale than residential or commercial PV and are often owned and operated by electric utilities.
Although utility-scale CSP plants were in operation long before solar photovoltaics became widely commercialized, solar photovoltaics have largely taken over this market, due to their declining costs. Global CSP capacity grew only 1. Concentrating Solar Power. Notes Solar collectors i. Source U. Biomass Biomass energy sources are used to generate electricity and provide direct heating, and can be converted into biofuels as a direct substitute for fossil fuels used in transportation.
Under some conditions, they may reject as much as 70 percent of all the solar energy they absorb. Indeed, scientists estimate that algae could grow as much as 30 percent more material for use as biofuel.
More importantly, the world could increase crop yields — a change needed to prevent the significant shortfall between agricultural output and demand for food expected by The challenge has been to figure out exactly how the photoprotection system in plants works at the molecular level, in the first picoseconds of the photosynthesis process.
A picosecond is a trillionth of a second. Critical to the first steps of photosynthesis are proteins called light-harvesting complexes, or LHCs. When sunlight strikes a leaf, each photon particle of light delivers energy that excites an LHC. That excitation passes from one LHC to another until it reaches a so-called reaction center, where it drives chemical reactions that split water into oxygen gas, which is released, and positively charged particles called protons, which remain.
If proton buildup indicates that too much sunlight is being harvested, the LHCSR flips the switch, and some of the energy is dissipated as heat. When a passing cloud or flock of birds blocks the sun, it could switch it off and soak up all the available sunlight. As a result, plants reject a lot of energy that they could be using to build more plant material.
Much research has focused on the quenching mechanism that regulates the flow of energy within a leaf to prevent damage. Optimized by 3. First, it can deal with wildly varying energy inputs. And it can react to changes that occur slowly over time — say, at sunrise — and those that happen in just seconds, for example, due to a passing cloud.
Researchers agree that one key to quenching is a pigment within the LHCSR — called a carotenoid — that can take two forms: violaxanthin Vio and zeaxanthin Zea. Conversion from Vio to Zea would change various electronic properties of the carotenoids, which could explain the activation of quenching. That type of fast change could be a direct response to the buildup of protons, which causes a difference in pH from one region of the LHCSR to another. Clarifying those photoprotection mechanisms experimentally has proved difficult.
Focusing on the LHCSR found in green algae and moss, they examined what was different about the way that stress-related proteins rich in Vio and those rich in Zea respond to light — and they did it one protein at a time. In earlier research, they had figured out how to purify the individual proteins known to play key roles in quenching.
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