What is the best solar collector?

What qualities should we consider when selecting a solar thermal collector?

Are two:

1- Its constructive qualities. Determines the durability and architectural integration possibility.

2- His energetic qualities. Determines economic performance.

In some respects both qualities are interrelated.

A good solar collector is one who possesses both qualities well balanced for the intended application.

There is no use a solar collector with an extraordinary energy intake if their constructive qualities fail or degrade quickly, since the profitability of these facilities is measured in the medium term.

There is no use a solar collector with extraordinary constructive qualities if their energetic qualities fail, because, simply, it is not fulfilling its main task.

By observing the solar collector performance curve, we see that it depends on a variable which is the temperature T, which in turn depends on the solar radiation I, on solar collector fluid inlet temperature Te and on ambient temperature Ta.

That is, the performance of a collector depends:

– On one side of the weather conditions, given by I and Ta,

– On the other side of the working conditions, that is, of what it is used, given by Te.

Therefore, when selecting a collector must be considered:

1) The application will have (only ACS, only heating, hot water and heating, pool heating, etc.).

2) Climatic and radiation conditions of facility location.

3) Models performance curves.

4) Equipment price.

5) The economic profitability (based purely on the relationship between price and yield) and investment recovery period.

6) Its construction quality.

You need to balance construction quality with energetic quality.

There is an open debate among professionals about which of the two most used collectors technologies is the most appropriate: flat or vacuum tube collector?

Those who opt for vacuum tube collectors consider them more advanced and argue that in the future this technology will eventually displace definitely flat plate collectors because of their better performance.

The increased cost gap of vacuum tube collectors respect to flat collectors has been reduced and we can find collectors of both technologies at the same price.

Supporters of the vacuum tube collectors consider opting for them is compensated, because by offering higher performance per m2 we will need to purchase less collectors.

This is not necessarily true, especially in small facilities:

In a small facility that only provides ACS with good weather and radiation conditions, flat plate collectors performance and profitability will be greater.

As you increase the size of the installation, the vacuum tube collector highest performance will offset the lower absorbing surface.

We will also consider building integration of vacuum tubes direct flow collectors (U-Pipe) that can be placed vertically covering a façade or balcony.

In short, a properly trained professional must assess based on the following factors choosing one or the other technology:

• Specific requirements of the installation

• Location climatology in every season

• Previous experience

• Budget availability.

You can find content like this in the Technical – Commercial Solar Thermal Energy Manual by Sopelia

Cuba Solar Thermal

The Cuban population spends between 529 and 791 GWh/year (6% of electricity) to heat water.

Considering the housing technical conditions and water service stability, 1 million Cuban families could receive hot water service using solar energy.

The first ad written in Spanish about commercial solar thermal technology, published in a mass medium communication was held in a Cuban newspaper in the 1930s.

The equipments introduced at that time were mainly from US and its high costs made them only available to economically advantaged clases of the country.

In 1978 a polygon was established to evaluate solar heating systems and the Cuban Standard for systems installation was approved in 1987.

In that period, first models adapted to island climatic conditions was developed and Cuban patent for a solar thermal compact system was obtained in 1979.

Between 1982 and 1991 they were built and installed over 13.000 solar thermal water heating systems in kindergartens and other social institutions. Most of these systems are now out of service because maintenance and technological problems.

From 1992 to 2006 about 4.000 flat collectors and compact equipments, several imported, were installed and were performed efforts to manufacture in the country.

In 2007 Chinese vacuum tube equipments were acquired for pilot test performing purpose.

Approximately 85% of the installed capacity corresponds to the tourist hotel sector.

Solar thermal systems for applications such as drying of agricultural and industrial products are also used.

The solar energy research centers carry over 2 decades working on solar drying technologies development models for timber, medicinal plants, grains, seeds and other products that now allow industrial use of these cameras and provides great economic benefit.

Very advanced solar dryers for tobacco drying and curing technologies developing have also succeeded.

The mentioned centers also work in the use of solar energy in controlled climate chambers for vegetables production and high quality seeds, refrigeration and cooling. The research focuses on potatoes, tomatoes and other products production that currently Cuba is forced to import.

Solar business in Cuba and Latam with Sopelia

Solar Creativity

When Federico Redin answered the phone call at his office in Bahia Blanca (Argentina) he was happy because it was to request their installation services in a new solar energy project.

But when he came to the house where the project would be located, he realized that the facility had some complexity.

It was a continuous use indoor pool with bathroom, dressing room and kitchen.

The pool was closed with rustic solid brick walls, aluminum DVH low quality openings in the enclosure and transparent polycarbonate roof. A challenge.

Piscina

After the visit, which solution adopt to optimally configure the installation was going around in his head.

Appealing to the characteristic creativity of Argentine people, Federico took an unconventional solution: swimming pool conditioning by floor heating (in the transit zones of the enclosure and in the pool itself).

In this way it would achieve heat the pool regardless of the type of water containing the glass and more efficiently, since conventional pool heating has the negative inertia of moving water.

By heating the pool water with a conventional boiler the water is set into motion with the same pool pump, causing cooling it by this movement; which decreases the overall installation performance.

Therefore, a more powerful source of energy and more thermal reaction is needed.

We know that using solar energy do not have a large thermal reaction, ie the heating time is slower.

By heating the pool with underfloor heating water turns hot through the concrete, once in regime, it has more thermal inertia and allows solar energy to maintain that regime.

The radiant “glass” pool and the transit floor area of the enclosure receive input from a conventional gas boiler, which is responsible for putting installation in system, and 7 heat pipe collectors supplying directly fluid to the circuit (without heat exchanger) that transfers heat in sunshine.

Colectores I

Temperature is regulated with a mixing thermostatic valve to not degrade the soil at high temperatures.

The system has a thermostat for transit zones and a thermostat for swimming pool water.

Then room or water temperature are discriminated with electric heads located at the underfloor heating collector, separating pool and transit zones of the enclosure.

The pool has a natural salt chlorination system (salt water 5%) thus avoiding the use of chlorine.

Caldera

Having 2 separate circuits (the pool and underfloor heating), we protect the boiler to heat salt water, which quickly will cause severe and irreversible damage to it.

Federico Redin is Sopelia facilities expert advisor.

Solar Cuba

Cuba is one of the last bastions that refuses to adopt the capitalist system.

This implies virtually the absence of private initiative and as a result of this a great deficiency in infrastructure.

The most common is to make a simplistic association of ideas of “limited resources = poor capabilities.”

Nothing further from reality.

As in other areas (like medicine), in the field of solar energy in Cuba are people with experience and good know-how.

On one hand we have the importance that Cuban gives to “have a say” and on the other hand we have the “times” in which things in Cuba move and respect that we must have free of prejudices about political culture.

Cuba needs to take firm steps toward energy independence by implementing a series of initiatives that are a future investment to counter the problems that have to oil stock up and the harm this means for the country’s economy.

In 2012 Cuba had in its energy matrix 4% of renewable energy and the expectations are to meet the 10% clean energy sources by 2020.

The renewable sources use has helped communities to reduce ecosystem pressure and deforestation caused by the massive use of firewood.

In the country currently operate 13 wind farms and 19 bioelectric plants providing 633 and 755 MW, respectively, to the national grid system.

Energy sovereignty is feasible with 1,100 MW wind power potential and high solar radiation received on its territory located in the Tropic of Cancer, reaches 5 kWh/m2 daily radiation (1.825 kW/m2 per year).

The first experiences in solar energy incorporation have been linked to rural electrification projects. Since the late 80s and early 90s, a program was initiated with the goal of bringing electricity to all rural mountainous and inaccessible regions to improve the quality of its inhabitants life.

After thawing relations initiated in December 2014 by Raul Castro and Barack Obama and the reform process initiated by Castro in 2008 (creation of Mariel special development zone and new Foreign Investment Law) the new economic climate favors the renewable energies development with the presence of some 100% foreign companies.

The expected increase in island tourism demand will cause construction activation, especially for hotels, boosting industry participation in the renewable energies development.

Cuba set a target of 700 MW PV to reach 24% renewables by 2030, reduce their energy costs and diversify its current energy mix in which 94% of electricity production is covered by fossil fuels (about 50.000 barrels a day of own production + 75.000 imports).

The Abu Dhabi Development Fund will enable Cuba to diversify its energy matrix and increasing renewable energy, particularly solar and wind.

This fund, which provides financial support to developing countries, will support a project to generate 10 MW of solar energy, which will increase by 50% the current installed capacity.

It also promotes an ongoing project until 2017 to desalinate water incorporating photovoltaics and small wind technology in new plants.

Solar energy business in Latam with Sopelia

Costa Rica Solar PV

The photovoltaic energy in Costa Rica began in 1991 with a pilot project in two indigenous “palenques” from the canton of Siquirres.

Then it spread to places like Península de Osa, Isla Caballo, Dos Bocas de Aguirre, Punta Burica de Golfito, Talamanca, Parque Nacional Volcán Chirripó, Rincón de la Vieja and some Guanacaste zones.

The Miravalles Solar Park was the first major solar electricity plant in Costa Rica and was the largest in Central America when being inaugurated, with a capacity of 1.2 GWh / year.

From Guideline NO14 MINAET the “Pilot Plan for Self Distributed Generation” ICE Group was created.

Many Costa Ricans began to install solar panels on homes and industries and more than 350 requests for interconnection were done, emerged a budding PV market in the country.

In February 2015 ICE Group closed its distributed generation pilot plan, indicating that it had reached its installation limit (10 MW).

Thereafter, users can not made new applications for interconnection.

Distributed generation projects were in the air, which has led to an atmosphere of uncertainty in the sector.

ARESEP Board approved in February 2015, with the corresponding calculation methodology, an access fee which covers all expenses incurred by distributors.

Industry sources said it was an excessively high rate, including maintenance and operating costs not related to distributed generation.

They also criticized the need to implement two measuring devices for subscribers, increasing implementation and billing costs associated with the distribution company.

It is important to unblock this situation to achieve the objectives of the National Development Plan and the VI National Energy Plan 2012-2030.

The solution could be found to continue allowing the interconnection of all stakeholders to the network, reviewing the methodology for calculating the access tariff and reviewing the approach to the need to use 2 measuring devices.

The fixed rates were also rejected by the distributors and the Costa Rican Solar Energy Association.

Regulating the incorporation of photovoltaics to the electricity grid is not easy. There are 3 very different interests (consumers, companies in the solar sector and electricity distributors).

What is clear is that if the legislation reduces the number of users interested in distributed generation, does not fulfill its mission.

Regulation should facilitate procedures for simple and speedy interface for any user, minimizing arbitrariness of either party.

In March 2016 ARESEP set new tariffs for distributed generation access.

How will be charged? It will be based on energy removal. It will not be charged for the energy generated by producer-consumer and used directly in self consumption form.

Time will tell whether the methodology established really meets the objective of encouraging the production of solar or wind energy.

In the case of large photovoltaic generation plants selected under the 7200 Law a very striking situation arises.

ARESEP announced the increase of rate bands established for bidders in July 2015 from $ 7.46 and $ 17.80 kW / h to $ 7.95 and $ 19.08 kW / h.

This increase will affect final energy consumer.

What is striking about this is that none of the four developers selected by the ICE requested any increase. This is a “gift” at final energy consumer expense.

This regulator proposal for increase 6.5% rates for a generation technology that every day is cheaper raises many suspicions.

Where Is Solar Industry in Latam ?

The solar market in South America is one of the most promising in the world.

As energy consumption soars, companies, governments and consumers are looking for ways to make power and heat generation more affordable. Decision makers at all levels are preparing to start work on future solutions to satisfy the new energy thirst in the region.

The solar market in Brazil shows enormous potential, being globally considered one of the most promising markets in the solar industry future.

Chile is a leader in the region and Uruguay is an example for other countries.

These days, Argentina stands as the land of opportunities for the solar sector in order to recover lost time and it seems that Colombia travels the same path.

Sopelia and Intersolar South America have reached a collaboration agreement to be Media Partners.

Intersolar South America became the fifth event of Intersolar, the solar industry world leading exhibition series.

The international exhibition and conference for the solar industry in South America will be held at the Expo Center Norte in Sao Paulo, Brazil between 23 and 25 August 2016.

It has focused on the areas of photovoltaics, PV production technologies, energy storage and solar thermal technologies.

Since its founding, Intersolar has become the most important industry platform for manufacturers, suppliers, distributors, service providers and members of the solar industry.

With 9,000 visitors from 34 countries and over 800 conference attendees, Intersolar South America 2015 attracted more than twice its expected attendance, becoming the largest exhibition and solar conference in South America.

115 exhibitors from 11 countries presented their products in 2015 (an increase of 60% compared to 2014) and gave very positive feedback on their testimonies.

The meeting is a combination of local and international experience.

Intersolar South America meets the photovoltaic sector to discuss the current status and trends in strategic photovoltaic markets in South America, as well as technology and new business opportunities innovations.

The event is an important meeting point for professionals throughout the entire photovoltaic value chain, and is much more relevant, given the recent strong growth of PV markets in South America.

2016 Intersolar South America will be developed alongside ENIE, the largest exhibition of Brazil for electrical installations, between 23 and 25 August, making the biggest event so far this year.

The signed agreement between Sopelia and Intersolar South America makes this event an engine in itself and a key exhibition platform for the solar industry in Sao Paulo in 2016.

More information www.intersolar.net.br

Costa Rica Solar Thermal

In mid-2015 was held in San Jose, Costa Rica an international event to bring together experts from different countries to share experiences on solar thermal technology developed in their areas.

The forum was jointly organized by the International Renewable Energy Agency (IRENA), the Latin American Energy Organization (OLADE), the Costa Rican Electricity Institute (ICE) and the National Metrology Institute of Germany (PTB).

The forum aimed to bring together experts to support the implementation of mechanisms for quality assurance in order to increase confidence in the technology and spur development, issues of products control, installations and installers, and a visit to the laboratory of solar energy and energy efficiency facilities of the Costa Rican Energy Institute was held.

The most important technical standards of the sector in Costa Rica are:

INTE * 03/01/28 / 2013. Solar thermal systems and components. Solar collectors. General requirements

INTE * 03/02/28 / 2013 Thermal solar systems and their components. Prefabricated systems. General requirements

INTE * ISO 9459-2 / 2013 Solar Energy. Systems for domestic water heating. External test methods for the characterization and yearly performance prediction of solar systems.

In Costa Rica, 41,3% of households use hot water systems (ACS), which mostly operate with electric power.
These systems represent an estimated national consumption of over 250 GWh / year.

It is very evident the need to establish a set of policies and incentives in order to achieve mass use of solar thermal technology in the residential sector.

These should include a technology implementation strategy, covering regulatory aspects, technical training and creation of laws governing the sector.

The aim would be to create a framework to introduce solar thermal systems to replace electric water heating equipment.

The country has approximately 1,200,000 homes for about 4,500,000 inhabitants (3,75 persons / household), of which only 3% are multifamily housing.

It follows that the basic ACS system for the average residential sector of Costa Rica with country radiation levels, would be payed at a more than reasonable time.

One of the most important facilities is located in a Tamarindo (Guanacaste) hotel.

A total of 164 collectors (330 m²) and 25,000 liters storage supplies hot water to 240 rooms and an industrial laundry, generating 529,600 kWh annually.

The investment will pay off in just 36 months with the savings generated.

Solar Costa Rica

Between 2006 and 2013, Costa Rica attracted more than U$D 1,700 million for renewable energies projects financing.

In 2013, a record of U$D 600 million was allocated to renewable energy. About 40% were allocated to non-hydroelectric renewable energy, especially wind power.

The electrical system of Costa Rica was 100% renewable in early 2015.

This was made possible by rain and by the strong commitment to renewable energy made in the Central American country.

According to the Costa Rican Electricity Institute, during the first 75 days of the year it was unnecessary to use fuel to feed the power grid of the country.

With reservoirs (Arenal, Cachí, La Angostura and Pirrís) full and what was generated in geothermal, wind, solar and biomass; thermal plants remained as a contingency alternative had not to resort.

Costa Rica has always the greener energy matrix in Central America with 80% coming from hydroelectric and 20% from renewables (mainly wind and geothermal).

One key to this development has been the integration into the Renewable Energy and Energy Efficiency in Central America (4E) Program, implemented by the International Cooperation Office of German government, by the General Secretariat of the Central American Integration System (SG -SICA), which works to promote a clean matrix in the region.

The problem is that too depends on the weather. If it does not rain enough, the water shortage creates a problem.

Costa Rica is proposed that its energy is completely clean by 2021. Currently, about half of the primary energy sources are renewable.

The country implemented two mechanisms to facilitate the penetration of renewables.

The first, a specific auctions system by technology that allowed to increase the hiring of additional capacity.

The second, a program to encourage consumers local generation who can sell excess energy to the grid.

However, no progress has been made in solar generation.

The Regulatory Authority for Public Services (ARESEP) proposed a price band for new companies that produce electricity on a solar photovoltaic large scale.

They were discussed in June 2015. The rates approved applies for all plants with capacities equal to or less than 20 MW, in accordance with the provisions of the 7200 Law, which regulates electricity trade between the ICE and private generators.

The intention is to allow private providers to obtain enough income to cover their operating costs, to recover the investment and a reasonable return for the level of risk associated with the electricity generation.

The average cost of the investment, the average cost of operation, the plant factor and the performance are calculated to determine the rate.

With this data rate is calculated with an upper and lower limit. Most of the information used comes from a study by German aid agency GTZ.

The band values will be reviewed once a year by fixing the ordinary procedure, which will begin on the first working day of February each year.

The small-scale generation to consumption is regulated by the POASEN Statement for levels at or below 1 MW generation.

Solar PV Colombia

The photovoltaic solar energy in Colombia began with the Rural Telecommunications Program and the National University technical assistance, in the early 80s.

In this program, 60 W small photovoltaic generators for rural radio telephones were installed.

In 1983 it had installed 2.950 systems. Then, the power was increased to 3-4 kW systems for earth satellite dishes.

Many companies began installing systems for telecommunications services and solar systems are currently used in microwave relay, buoys, remote stations and military bases.

These systems are now essential for country’s telecommunications.

Between 1985 and 1994 48.499 solar modules equivalent to about 2 MW power were imported. Of these, 21.238 modules with 844 kW output were used for telecommunications projects and 20.829 modules with 954 kW output for rural electrification.

On a 248 sample of these systems, 56% worked without problems, 36% worked with some problems and 8% were out of service.

Problems were found in the lack of a minimum maintenance, supply of replacement parts and undersized systems. Rather than being a technical problem, the problem is service quality and customer service. These shortcomings persist today.

In electrification programs, the standard isolated system has consisted in a 50-70 W module, a 60 to 120 Ah battery and a charge controller. These small systems provide power for lighting, radio and TV, covering the basic needs of rural population.

The current cost of this system is around U$D 1200-1500, mainly affected by the high costs of installation in remote areas.

According to the IPSE (Institute for the Promotion of Energy Solutions) there are currently more than 15.000 systems installed for these applications.

Something like what happened with solar termal case happened with solar photovoltaics in Colombia. The market had its boom in the late 80s with the mentioned rural telecommunications program.

Then in the 90s public order difficulties slowed their development, whose growth is estimated at 300 kW / year (the current installed capacity would be around 9 MW).

Photovoltaic electricity generation has huge prospects, considering that about 1 million families lack electricity service in Colombia rural areas.

Colombians achievements are very modest and current development does not match its potential. Valuable time has lost.

The most representative projects are:

* Solar-diesel hybrid system. Titumate – Unguia – Choco. Launched in June 2008

* Solar PV system of 125 kW with 2 axes 10 followers, 8 of which are located in the Upper Guajira and 2 in Isla Fuerte. Launched in September 2009

* Solar-wind hybrid system. Nazareth, La Guajira department. Launched in June 2008

* Solar PV systems for 451 homes in rural area without electricity. San José del Guaviare. Launched in November 2009

One of the most important facilities is projected in Providence, which consist in the construction, operation and maintenance of 60 MW solar photovoltaic plant and associated facilities.

The plant will be located near the international airport in Zacatecoluca, La Paz and is expected to generate 159.000 MW / year to be sold to 7 companies, which distribute electricity to final consumers.

Argentina: The awakening of the sleeping giant

After more than 10 years of lethargy caused by the populist “siesta”, the renewable energy sector of Argentina needs to regain lost time.

Such projects development requires a context of political and economic stability and we could say, using the football jargon, that Argentina is “preparing the stadium for playing the match”.

Next Friday 22nd April the country is preparing to cancel the debt with creditors that did not enter 2005 and 2010 swaps, and thus leave behind a default that lasted nearly 15 years.

The other leg of the table is the 531 decree of March 30rd 2016 that establishes mechanisms for achieving the goals of 8% in 2017 and 20% in 2025 (referred in 27,191 law) of electricity generation through renewable sources.

Making a flashback we can infer that to achieve such ambitious goals, the speed will be exciting:

In 2006 was set as a target for 2016, that Argentina would reach 8% of electricity generation by renewable sources.

The numbers indicate that so far in 2016 barely exceeded 2%.

That is, just over 25% of the objective reached.

And as has already occurred in the sector of renewable energies elsewhere, when hurry is need who take the initiative will get the duck to the water.

Decree 531:

* Create the trust fund of U$D 820 million “Fund for the Development of Renewable Energies” (Foder).

* Set purchase mechanisms (including hiring, self-generation or cogeneration or participation in a joint procurement mechanism) for users with power demands equal to or greater than 300 kW; which should cover at least 8% of total electricity consumption from renewable sources by 31 December 2017.

* Contemplate the possibility of quotas for technologies in bids (price “may be established” in US dollars).

* Establish more favorable conditions for national components use in projects and are planned instruments to encourage local production of components.

Sopelia develops activity in the Argentine solar sector since 2011 with its local partner Puerto Hueche S.R.L .. Engineer Nahuel Rull says:

“Can access the “RENEWABLE ENERGY PROMOTING SYSTEM” individuals domiciled in the ARGENTINA REPUBLIC and legal entities created in the ARGENTINA REPUBLIC, holders of investment projects of electricity generation from renewable sources”.

“The company provides the following services:

– Presentation to the Enforcement Authority of documentation needed to obtain the Certificate of Inclusion in the “RENEWABLE ENERGY PROMOTING SYSTEM” and to the allocation of promotional benefits

– Individual renewable sources electricity procurement

– Solar energy self-generation and cogeneration projects management

– Management of joint purchases of renewable electricity to the body designated by the Enforcement Authority.

– Foreign investors and EPCs support”

For not flooded fields or lands owners, located in northern Argentina that have 5% maximum slope, an attractive business opportunity presents itself: the photovoltaic solar energy. Also for large roofs or covers owners of the same region.

For investors who want to increase their portfolio of renewable energy projects, it is time to focus on Argentina.

For users with power demands equal to or greater than 300 kW countdown began: have 20 months to consume at least 8% of their electricity total consumption from renewable sources.

Starting gun sounded.