One- to 10-kW turbines can be used in applications such as pumping water. Wind energy has been used for centuries to pump water and grind grain. Although mechanical windmills still provide a sensible, low-cost option for pumping water in low-wind areas, farmers and ranchers are finding that wind-electric pumping is more versatile and they can pump twice the volume for the same initial investment. In addition, mechanical windmills must be placed directly above the well, which may not take advantage of available wind resources. Wind-electric pumping systems can be placed where the wind resource is the best and connected to the pump motor with an electric cable. However, in areas with a low wind resource, mechanical windmills can provide more efficient water pumping.
Low Temperature Geothermal refers to the use of the outer crust of the earth as a Thermal Battery to facilitate Renewable thermal energy for heating and cooling buildings, and other refrigeration and industrial uses. In this form of Geothermal, a Geothermal Heat Pump and Ground-coupled heat exchanger are used together to move heat energy into the earth (for cooling) and out of the earth (for heating) on a varying seasonal basis. Low temperature Geothermal (generally referred to as "GHP") is an increasingly important renewable technology because it both reduces total annual energy loads associated with heating and cooling, and it also flattens the electric demand curve eliminating the extreme summer and winter peak electric supply requirements. Thus Low Temperature Geothermal/GHP is becoming an increasing national priority with multiple tax credit support and focus as part of the ongoing movement toward Net Zero Energy. New York City has even just passed a law to require GHP anytime is shown to be economical with 20 year financing including the Socialized Cost of Carbon.
A more recent concept for improving our electrical grid is to beam microwaves from Earth-orbiting satellites or the moon to directly when and where there is demand. The power would be generated from solar energy captured on the lunar surface In this system, the receivers would be "broad, translucent tent-like structures that would receive microwaves and convert them to electricity". NASA said in 2000 that the technology was worth pursuing but it is still too soon to say if the technology will be cost-effective.
Concentrated solar power plants may use thermal storage to store solar energy, such as in high-temperature molten salts. These salts are an effective storage medium because they are low-cost, have a high specific heat capacity, and can deliver heat at temperatures compatible with conventional power systems. This method of energy storage is used, for example, by the Solar Two power station, allowing it to store 1.44 TJ in its 68 m³ storage tank, enough to provide full output for close to 39 hours, with an efficiency of about 99%.
Another economic measure, closely related to the energy payback time, is the energy returned on energy invested (EROEI) or energy return on investment (EROI), which is the ratio of electricity generated divided by the energy required to build and maintain the equipment. (This is not the same as the economic return on investment (ROI), which varies according to local energy prices, subsidies available and metering techniques.) With expected lifetimes of 30 years, the EROEI of PV systems are in the range of 10 to 30, thus generating enough energy over their lifetimes to reproduce themselves many times (6–31 reproductions) depending on what type of material, balance of system (BOS), and the geographic location of the system.
Then the faster the coil of wire rotates, the greater the rate of change by which the magnetic flux is cut by the coil and the greater is the induced emf within the coil. Similarly, if the magnetic field is made stronger, the induced emf will increase for the same rotational speed. Thus: emf ∝ Φn. Where: “Φ” is the magnetic-field flux and “n” is the speed of rotation. Also, the polarity of the generated voltage depends on the direction of the magnetic lines of flux and the direction of movement of the conductor.
Energy engineering Oil refinery Fossil-fuel power station Cogeneration Integrated gasification combined cycle Electric power Nuclear power Nuclear power plant Radioisotope thermoelectric generator Solar power Photovoltaic system Concentrated solar power Solar thermal energy Solar power tower Solar furnace Wind power Wind farm High-altitude wind power Geothermal power Hydropower Hydroelectricity Wave farm Tidal power Biomass
“New Wind May Be Cheaper than Old, Reliable Coal” • Wind farms have cost less to build and operate than coal-fired power plants for some time. The trend of lower costs for renewables has crossed a threshold: it is sometimes cheaper to build a brand new wind facility than keep an old coal plant burning, according to Lazard Ltd. [Casper Star-Tribune Online]
Bioethanol is an alcohol made by fermentation, mostly from carbohydrates produced in sugar or starch crops such as corn, sugarcane, or sweet sorghum. Cellulosic biomass, derived from non-food sources such as trees and grasses is also being developed as a feedstock for ethanol production. Ethanol can be used as a fuel for vehicles in its pure form, but it is usually used as a gasoline additive to increase octane and improve vehicle emissions. Bioethanol is widely used in the USA and in Brazil. Biodiesel can be used as a fuel for vehicles in its pure form, but it is usually used as a diesel additive to reduce levels of particulates, carbon monoxide, and hydrocarbons from diesel-powered vehicles. Biodiesel is produced from oils or fats using transesterification and is the most common biofuel in Europe.
Jump up ^ Faunce, T. A.; Lubitz, W.; Rutherford, A. W. (Bill); MacFarlane, D.; Moore, G. F.; Yang, P.; Nocera, D. G; Moore, Tom A; Gregory, Duncan H; Fukuzumi, Shunichi; Yoon, Kyung B.; Armstrong, F. A.; Wasielewski, M. R.; Styring, S. (2013), "Energy and environment policy case for a global project on artificial photosynthesis", Energy & Environmental Science, 6 (3): 695–698, doi:10.1039/C3EE00063J, archived from the original on 16 August 2013
Features:Low wind speed start-up(2m/s), high wind power utilization, light,cute, low vibration.Human-friendly design,easy to install and maintain.Blades using reinforced glass fiber, helped with optimized structure and aerodynamic shape, it enhanced wind power coefficient and power generating capacity.Using patented permanent magnet generator and special stator, it effectively reduces torque resistance and guarantees the stability.The 24V DC 400W wind turbine is an eco.
Green Energy Corp’s GreenBus® software interoperability platform enables the adoption of evolving Smart Grid technologies and integration with legacy power and communications infrastructures. Microgrid developers can now design and implement an architecture that supports advanced technology adoption over time, while realizing the business benefits incrementally.
Home wind turbines are electric generators that convert wind energy into clean, emission-free power. Although most large wind farms exist to power certain towns and communities, there are also smaller wind turbines for homes and homeowners. These smaller turbines can be installed on any part of your property to cover some or even all of your monthly energy needs.
Climate change and global warming concerns, coupled with high oil prices, peak oil, and increasing government support, are driving increasing renewable energy legislation, incentives and commercialization. New government spending, regulation and policies helped the industry weather the global financial crisis better than many other sectors. According to a 2011 projection by the International Energy Agency, solar power generators may produce most of the world's electricity within 50 years, reducing the emissions of greenhouse gases that harm the environment.
Above this rated speed, the wind loads on the rotor blades will be approaching the maximum strength of the electrical machine, and the generator will be producing its maximum or rated power output as the rated wind speed window will have been reached. If the wind speed continues to increase, the wind turbine generator would stop at its cut-out point to prevent mechanical and electrical damage, resulting in zero electrical generation. The application of a brake to stop the generator for damaging itself can be either a mechanical governor or electrical speed sensor.
“California Looks to Stationary Energy Storage as a Solution to Peaker Plants” • Central California electric utility Pacific Gas & Electric is planning to replace three old natural gas power plants in its network with stationary energy storage installations from Tesla. California is looking to add 1.3 GW of storage to its power grid by 2020. [CleanTechnica]
The most significant barriers to the widespread implementation of large-scale renewable energy and low carbon energy strategies are primarily political and not technological. According to the 2013 Post Carbon Pathways report, which reviewed many international studies, the key roadblocks are: climate change denial, the fossil fuels lobby, political inaction, unsustainable energy consumption, outdated energy infrastructure, and financial constraints.
Many industrialized nations have installed significant solar power capacity into their grids to supplement or provide an alternative to conventional energy sources while an increasing number of less developed nations have turned to solar to reduce dependence on expensive imported fuels (see solar power by country). Long distance transmission allows remote renewable energy resources to displace fossil fuel consumption. Solar power plants use one of two technologies: