The solar thermal power industry is growing rapidly with 1.3 GW under construction in 2012 and more planned. Spain is the epicenter of solar thermal power development with 873 MW under construction, and a further 271 MW under development. In the United States, 5,600 MW of solar thermal power projects have been announced. Several power plants have been constructed in the Mojave Desert, Southwestern United States. The Ivanpah Solar Power Facility being the most recent. In developing countries, three World Bank projects for integrated solar thermal/combined-cycle gas-turbine power plants in Egypt, Mexico, and Morocco have been approved.
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A 2014-published life-cycle analysis of land use for various sources of electricity concluded that the large-scale implementation of solar and wind potentially reduces pollution-related environmental impacts. The study found that the land-use footprint, given in square meter-years per megawatt-hour (m2a/MWh), was lowest for wind, natural gas and rooftop PV, with 0.26, 0.49 and 0.59, respectively, and followed by utility-scale solar PV with 7.9. For CSP, the footprint was 9 and 14, using parabolic troughs and solar towers, respectively. The largest footprint had coal-fired power plants with 18 m2a/MWh.
With advanced technology being developed, cellulosic biomass, such as trees and grasses, are also used as feedstocks 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 United States and in Brazil. The energy costs for producing bio-ethanol are almost equal to, the energy yields from bio-ethanol. However, according to the European Environment Agency, biofuels do not address global warming concerns. Biodiesel is made from vegetable oils, animal fats or recycled greases. It can be used as a fuel for vehicles in its pure form, or more commonly 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. Biofuels provided 2.7% of the world's transport fuel in 2010.
There is one more area where buyers may get a false sense of security: Several states in the US have lists of “approved” wind turbines for their rebate programs. An example of this is the California list. The problem is that approval for this list, and the performance data provided (such as rated power and energy production) are essentially self-certified. The less-scrupulous manufacturers can ‘manufacture’ data and submit it under the pretence that it was measured. The only value of those lists is in telling you what rebates are available, they do not provide reliable turbine information.
How accurate are these numbers? This is the energy production a good horizontal-axis wind turbine can reach, if installed at the perfect site and height. These are the upper limit though, if your turbine produces anywhere near the number predicted by this table you should be doing your happy-dance! Most small wind turbine installations underperform significantly, in fact, the average seems to be about half of the predicted energy production (and many do not even reach that). There can be many reasons for the performance shortfall; poor site selection, with more turbulent air than expected often has much to do with it. The reports in the ‘real world’ section following below illustrate this point. Many small wind turbines do not reach 30% overall efficiency, some are close to 0% (this is no joke!), so these numbers have only one direction to go. For off-grid battery charging wind turbines you should deduct 20 – 30% of the predicted numbers, due to the lower efficiency of a turbine tied to batteries, and the losses involved in charging batteries.
It is possible to use any type of solar thermal panel (sheet and tubes, roll-bond, heat pipe, thermal plates) or hybrid (mono/polycrystalline, thin film) in combination with the heat pump. The use of a hybrid panel is preferable because it allows covering a part of the electricity demand of the heat pump and reduce the power consumption and consequently the variable costs of the system.
A parabolic trough consists of a linear parabolic reflector that concentrates light onto a receiver positioned along the reflector's focal line. The receiver is a tube positioned along the focal points of the linear parabolic mirror and is filled with a working fluid. The reflector is made to follow the sun during daylight hours by tracking along a single axis. Parabolic trough systems provide the best land-use factor of any solar technology. The SEGS plants in California and Acciona's Nevada Solar One near Boulder City, Nevada are representatives of this technology.
This solar resource map provides a summary of the estimated solar energy available for power generation and other energy applications. It represents the average daily/yearly sum of electricity production from a 1 kW-peak grid-connected solar PV power plant covering the period from 1994/1999/2007 (depending on the geographical region) to 2015. Source: Global Solar Atlas]