Green Power incorporates all aspects required to bring solar power to the market from a concentrated solar power plant:
- project origination
- field planning and feasibility studies
- business and project development (Concept studies)
- project financing
- engineering and design, procurement and construction (EPC)
- ownership (IPP)
- operations (O&M)
- asset management
The energy sector is facing a paradigm shift away from fossil fuels
Green Power focuses on the CSP technology (Concentrated Solar Power), also called STE (Solar Thermal Electricity), which consists in concentrating heat (from the sun) into one point. This way, steam is generated to drive the turbine. Furthermore, this type of plant can work constantly, as part of the heat is stored.
This allows for it to continue producing steam and supplying energy to the grid when there is a lack of solar irradiation.
Generation of bulk solar thermal electricity (STE) from concentrating solar power (CSP) plants is one of the technologies best suited to mitigating climate change in an affordable way, as well as reducing the consumption of fossil fuels. Unlike photovoltaic (PV) technology, CSP offers significant advantages from a system perspective, thanks to its built-in thermal storage capabilities. CSP plants can operate either by storing heat or by combination with fossil fuel generation (gas or coal); providing firm and dispatchable power available at times at the request of power grid operators, especially when demand peaks in the late afternoon, in the evening or early morning, or even when the sun isn’t shining.
Such an advantage helps optimize the transmission network, particularly in countries with a high consumption growth.
Thermal storage system & Dispatchability:
- avoid fluctuations in the power supply.
- continues to produce energy during hours when there is no solar radiation, i.e during the night.
- allows to move the production peaks according to demand.
Dispatchability is the ability of a power-producing facility to provide electricity that can be dispatched at required amounts of power on demand of the grid operator. Power plants with dispatchable generation can be turned on or off, or can adjust their power output on demand.
Dispatchability is one of the characteristics that makes CSP a favoured option among other renewable resources, thanks to its storage and the possibility of hybridisation, CSP plants can effectively follow the demand curve with high capacity factors delivering electricity reliably and according to plan.
Thermal Storage system allows provide power during periods of absence of direct solar radiation, so that periods of solar gain and the power supply does not have to happen at the same time. Besides, it allows discharge into the power network requires it, regardless of the direct radiation that is affecting the feedback system.
All CSP plants can store heat energy for short periods of time and thus have a “buffering” capacity that allows them to smooth electricity production considerably and eliminates the short-time variations that non-dispatchable technologies exhibit during cloudy days.
This makes our technology as competitive as conventional fossil fuel or nuclear power plants, but without the unecological emissions and with an unlimited source of free green energy – the SUN.
Commercially proven technology
With the first commercial plants in the U.S., CSP technology has been in use for over 30 years. Plants have improved over time and significant technological developments have led to cost reduction and higher efficiency. CSP is neither an experimental technology nor one undergoing testing, but rather a commercial solution that can be adapted to a variety of geographic locations.
CONCENTRATED SOLAR PLANT EXECUTIVE SUMMARY
CSP plants using ORC as heat to electricity conversion is widely known and used around the world. One of the key advantages is a cheap storage of energy, which enables production of electricity 24/7. Due to the low maintenance of the organic rankine cycle is a higher uptime seen compared to a steam rankine cycle.
The proposed system below use the best technologies available for producing cost effective solar electricity.
System overview
1. Solar irradiation gets concentrated and heats thermal oil. 2. The heated thermal oil is stored in a thermal storage. Enough heat for 24 hour production is collected during the solar hours. 3. The PowerPack ORC engine uses the energy difference between the stored heat and ambient temperature to produce electricity.
Solar thermal collectors
The solar thermal collectors as a whole is the largest part of the plant. A high concentration of the solar irradiation and high optical efficiency is crucial to reach high temperatures, which is why a nonlinear solution is selected. The collector technology is optimized for the temperature range of 150 to 500 °C. Components are sourced locally and manufacturing is performed on site, which lower production and transportation cost. The manufacturing is optimized for the site’s prerequisites.
Thermal storage
The heated thermal oil is stored in large tanks with a system configuration to enable a high separation between hot and cold thermal oil. Almost no thermal loss occur to ambient environment due to the ratio between tank wall and volume.
Thermal to electricity conversion
The solution for converting heat into electricity is a redesign of the traditional ORC-cycle allowing a significantly higher efficiency and power output. By only using thermal energy to create a pressure in a closed vessel is no electricity consuming pressure pump needed. The total need of heat for driving the process is often less than 1 % of the thermal input.
By optimizing the cycle for the local conditions is a high efficiency achieved at the same time as the maximum amount of the available heat is utilized, which decrease the size of the storage and increase efficiency of the solar thermal collectors.
Solar Power Plant for 24 hours per day production
In order to produce electricity during full time day and night requires storage of heat for conversion to electricity even when sun heat is not available. Requested area of sun collector area is depending on the sun irradiation strength. Collected sun heat is concentrated and stored in towers at quite high temperature for use 24 hours per day. The entire process must collect heat during sunny hours and store it during remaining hours until sun is back again.
With our system we take advantage of this physical facts and dimension the system sun collection area and heat storage capacity to feed the conversion process, making electricity out of heat. The conversion process also needs cooling water or cooling air for cooling and condensation the circulation warm gas from the turbine through the process cycle. The Power Pack solution we use is much more efficient than common ORC processes why requested sun collection area is less per produced kW of electric power.
Cooling and condensation
The efficiency is depending on temperature difference of inlet hot media and cold media. If availability of cooling water is limited the ambient air condition can be used to reduce need of water. In this case we offer a cooling tower solution with circulation water cooled by ambient temperature. This reduces the water flow consumption to a minimum.
Cooling Tower
Benefits
This process design is maximizing use of sun radiation from early rise to late set in evening. The sun collectors are dynamic controlled to collect sun heat during the full period. The heat is reflected and concentrated in modules giving high performance to the entire system. The thermal efficiency of the conversion process, Power pack, is on top on market and require less heat than common ORC systems per kW electricity supply. This means reduced requirement of foot print for sun collection.
The total benefit ends up in lowest investment cost per produced kWh over long period of time.
The Green Power – Greelec CSP system
The Green Power – Greelec CSP system is significantly more efficient than other systems as it operates without a circulation pump and other ancillary equipment usually associated with transfers of heated and cooled liquid medium. Oil is used in a closed system with little or no energy loss and the heated oil used to generate the electricity requires minimal energy to operate. Simply explained, the heat from the sun is collected and directed to a heat absorber using a mechanical and selfcleaning system of smart mirrors, with an in-built sun tracking technology to ensure maximum performance making it effective even in cloudy weather.
The entire construction of a Greelec installation is comparably simple and requires minimal maintenance. Despite the smart mirror system employed for the sun and thermal heat collection, they can in most cases be sourced and manufactured locally and as the mirrors can be mounted vertically, the ground for most plants does not need to be levelled, which typically is a requirement for photovoltaic plants. As our technology use an organic storage system and does not require or use any batteries for storage, it is environmentally more sustainable and substantially more cost effective relative to other systems.
CSP Technology systems generate solar energy by using mirrors or lenses to collect and concentrate sunlight or thermal heat. Electricity is produced by the heat driving a turbine connected to a generator. The CSP technology has historically been relatively costly, but the costing model is drastically coming down and the number of CSP power plants is increasing around the world. The CSP technology delivers electricity around the clock as it has an inbuilt storage system, and therefore does not need a supplementary energy source. It has a higher level of efficiency with fewer non-environmental parts used in the system.
Why the Green Power – Greelec CSP system? Our technology is revolutionary and meets the long term objective of clean energy solutions. Compared to other solar energy technologies, including that of other CSP systems and the PV technology, our CSP system is reliable and has a substantially higher efficiency while requiring minimal energy and maintenance to operate. With our unique storage solution, we can deliver electricity uninterruptedly without the use of any batteries or other supplementary sources, making it environmentally friendly and more sustainable than other renewable energy sources. Our technology requires minimal maintenance and a much smaller physical footprint than other solar energy systems, while still delivering a essentially higher efficiency. There are less construction costs involved as the ground does not need “levelling” to mount the solar collectors, and they can be mounted also in versatile terrains. The system is scalable for smaller kW to bigger MW infrastructure installations, and as the system collects heat from the sun, it operates also in cloudy weather.
Advantages with the Green Power – Greelec system:
o Delivers electricity around the clock, without the use of batteries o Is environmentally sustainable and cost effective o Built on a simple design and layout o Needs a smaller footprint than other solar systems o Is scalable from a few kW to 100 MW systems o Can be targeted for private homes and infrastructure projects o Does not need ground leveling o Requires minimal maintenance o Many parts can be sourced and manufactured locally o Is effective even in tropical cloudy weather o Can be operated in the most exacting and extreme conditions