nedjelja, 7. siječnja 2018.


The ten manufacturers examined here were responsible for over 43GW of new wind capacity in 2016, representing 76% of the global market, and amounting to nearly 20,000 turbines.Their cumulative capacity at the end of last year added up to 380GW, more than three quarters of the worldwide total.

With more normal service resumed in 2016, Vestas returned to the top. According to FTI Consulting, it installed nearly 9GW last year, taking 15.8% of the global market.

The key word here is "global" because Vestas was active in 34 markets in 2016, more than any other turbine maker, FTI Consulting says. There has been no let-up this year, with the company announcing substantial turbine-purchase orders in some hitherto unlikely places — from China and South Korea to Russia.

The US supplies the lion's share of the order book though, mainly for the highand medium-wind V100 and V110 2.0MW models.

Low-wind variants — with rotor diameters of 116 and 120 metres — were announced in April and will be in production next year.

The more Europe-centred 3MW platform is being upgraded for a nameplate capacity of 4.2MW with rotor diameters of 117, 136 and 150 metres.

Largely driven by the demands of competitive tendering auctions, especially in Germany, the main focus is on the medium- and low-wind models.

But the V117 will take the platform into typhoon territory for the first time, opening up coastal markets in China, Japan and Vietnam to the company.

The MHI Vestas offshore joint venture came of age in 2017 with the commissioning of Dong Energy's 258MW Burbo Bank Extension off England's north-west coast.

It was the first to deploy the V164-8.0MW turbine, but orders are in for UK, German and Dutch offshore projects.

A 9.5MW variant of the V164 was announced in the summer, which has already been specified for Innogy's 860MW Triton Knoll project in UK waters. The only bad news on the offshore front during 2017 was the loss through fire of the first 9.5MW V164 prototype installed at the onshore Osterild test site in Denmark.

Vestas's acquisition of independence service providers UpWind Solutions and Availon has paid dividends. Service orders rose from €1.8 billion in 2015 to €10.7 billion last year, the company reported.

Expanding the service operation is only part of the Vestas' strategy of looking beyond the core business of making and selling machines.

"We have definitely stopped seeing ourselves as merely providing turbines," says company vice president Morten Dyrholm. "We are looking at ourselves more and more holistically, as part of a larger electrical system where different technologies need to balance up against each other."

This is still very much a work in progress, although Vestas has been involved in a small-scale hybrid wind-solar and storage schemes. In September the firm confirmed it was working with electric vehicle maker Tesla on energy storage solutions. Pilot projects are planned for 2018, with commercial schemes to follow.

The merger of Siemens and Gamesa, which took effect on 3 April, created a new giant in wind-turbine manufacturing — one with 75GW of installed capacity across 90 countries, 27,000 employees, and a wide range of onshore and offshore hardware.

Six months later, however, and it is still unclear how Siemens Gamesa Renewable Energy (SGRE) will fuse its operations and product line-ups. The first casualty, not entirely unexpected, appears to be the Adwen 8MW offshore turbine, which fell under Gamesa's wing when nuclear group Areva quit the wind business.

Replacing the geared Adwen unit with the direct-drive SGRE 8MW turbine for France's first offshore projects effectively sounds the death-knell for the Adwen machine.

There may be a future for its gearbox, built by Siemens subsidiary Winergy, in future offshore turbine designs from other OEMs, but that is by no means certain.

Another casualty has been jobs, particularly in blade manufacture, where plants in Canada and Denmark have been closed or cut back. Around 1,500 jobs have been lost this year.

Both arms of the new entity have found the going hard in 2017. Gamesa has been hit by the slowdown in Brazil, and the sudden slump in India as state utilities switch from feed-in-tariffs to competitive tendering.

Siemens has been outgunned by Vestas and GE in the ultra-competitive US market, and has been slow to react to the new demands of the German auction system.

The new company looked in need of a big win, and found it as the leader in the consortium that won a 1GW order in Turkey with a bid of only €34.8/MWh over 12-13 years.

"At that price, they're welcome to it," was the off-the-record response of one rival OEM and bidder. The contract includes a commitment to set up manufacturing and research facilities in Turkey, employing mainly local people, and a 65% local content requirement.

The turbine portfolio looks cluttered. Gamesa offers a 2MW platform with rotor diameters ranging from 80 to 114 metres; a 2.5MW family with rotor diameters of 106-126m; and a 3.3MW machine with a rotor diameter of 132m. Siemens' geared 2.3-2.625MW onshore platform comes in at 101-120m. Its direct-drive onshore family now stands at 3.2-4.3MW with rotor diameters of 101, 108, 113, 120, 130, and 142 metres.

The situation is rather clearer offshore, where the direct-drive SWT-154 turbine, introduced as a 6MW model but now developed to 8MW, has only the MHI Vestas V164 for competition in the 7MW-plus sector.

These two turbines look set to dominate Europe's offshore market for the next decade, and are well-placed to exploit the nascent US offshore sector.

3. GE, US

The pull of the domestic market remains strong for GE, but the US turbine maker has been making solid progress of late in a number of other countries, particularly in the Asia-Pacific region.

In May, GE announced orders of nearly 200MW for two projects in China. June saw a deal with Mainstream Renewable Power to install 800MW in Vietnam. Highlights over the summer included a 153MW contract in Pakistan and a 453MW deal in Australia.

But the big opportunities lie in the US, well into its production tax credit phase-out boom.

According to Make Consulting's analysis, announced at the American Wind Energy Association's conference in May, 50GW of new wind power will be installed in the US by the end of 2020, plus another 7-8GW in repowering.

GE is aiming for a substantial slice of this market and will play hard to get it. It is now taking its chief competitor, Vestas, to the US courts in a patent infringement dispute.

The biggest order of the boom so far was announced in June - 800 2.5MW turbines for the Invenergy-developed 2GW Wind Catcher project in Oklahoma. Repowering deals include one worth roughly 500MW with PacifiCorp in Idaho.

GE's venture into offshore waters looks less clear-cut. The 6MW Haliade turbine, acquired with Alstom, started its commercial electricity-generating life at Deepwater Wind's 30MW Block Island site, commissioned in December last year.

Three more turbines are being installed at a demonstration project in China. Beyond that, there are orders for three French projects worth 1.5GW, which remain held up in legal disputes, and 396MW for a German project in the North Sea.

The Haliade's 6MW nameplate capacity and 150-metre rotor diameter already leave it well behind the MHI Vestas and SGRE competition, raising doubts over its long-term future.

Those doubts grew in May when it was revealed that the European Commission (EC) was investigating GE's takeover of blade maker LM Wind Power, approved by the EC only two months earlier, on the grounds that GE had initially submitted "misleading information".

GE allegedly told the EC that it was not planning to develop a 12MW offshore turbine, but European Union regulators had subsequently found evidence to the contrary. The investigation continues.

GE has been heavily dependent on its 1.7-1.85MW and 2.0-2.5MW workhorse platforms for sales. Its 3.2-3.8MW family, aimed at the European markets, especially Germany, has struggled to make headway against the competition from Vestas, Enercon and Nordex, all of which are now working on 4MW-plus turbines.

GE revealed some details of a new 4.8MW machine with a record-setting rotor diameter of 158 metres at September's Husum trade fair. Aimed at lowand medium-wind sites, it will be available with tower heights ranging from 101 to 161 metres.

Goldwind was the world's leading manufacturer in installed capacity in 2015, its 7.88GW taking it past Vestas and GE.

But a slowdown in the Chinese market meant it slipped to third in last year's rankings, and with the creation of Siemens Gamesa Renewable Energy (SGRE) in April, it falls to fourth.

Goldwind reported a 10% fall in revenue and a 21% drop in pre-tax profit in the first half of 2017 compared with a year earlier, compounding fears the slowdown in China may have on its results.

The company's cumulative installed capacity at the end of 2016 stood at just over 38GW, but only 1.4GW of that is outside China.

In 2016, it supplied turbines to three markets outside China — more than any of its domestic rivals — and that looks set to rise in the coming years.

The shining light in its international arsenal is the Goldwind Americas subsidiary. Towards the end of last year, the firm won a 1.87GW deal for developer Viridis Eolia's multi-phase project in Wyoming. Delivery of the 2.5MW and 3MW turbines is due between now and 2022.

Elsewhere, over the summer Goldwind signed a memorandum of understanding with Saudi Arabian government agencies to research investment opportunities and potential manufacturing sites.

The company is adding storage to its catalogue. In August, Goldwind signed a letter of intent with Swedish storage company SaltX to develop a "solution for wind power with integrated energy storage". Goldwind plans to join SaltX's thermal energy-storage technology in a "megawatt-scale system" in Beijing.

Another year like 2015 may be a few years away for Goldwind, but it has realised to reach those heights again it needs to have a multi-pronged attack and cannot rely simply on quantity to secure a market position. It takes innovation and diversity as well.

Speaking at the Hannover Messe trade fair in April, Enercon's managing director, Hans-Dieter Kettwig, forecast gross performance of roughly €5.5 billion for 2017, with installations expected to reach up to 4GW. This is an increase from the 3.6GW installed in 2016, as reported by FTI Consulting.

Kettwig's comments offer a rare glimpse of the financial health of Enercon. Operating as an independent conglomerate of limited-liability companies, it is immune to the pressures of quarterly public reporting, unlike its stock-exchange-listed competitors.

Enercon's presence in 26 markets last year was second only to Vestas, according to the FTI figures, indicative of the work it does in smaller markets, including Bolivia, Costa Rica, Estonia, Taiwan and Vietnam. Historically it has steered clear of the US and China.

Equally notable is that its most popular turbine was the E115-3MW - all of the other top OEM's biggest-selling models were 2.4MW or smaller.

This year saw Enercon's re-entrance to the Indian market, following the completion of a decade-long legal dispute with its former joint-venture partner in the country, now trading as WindWorld India.

Enercon wants to refurbish 1,200 of its turbines on the subcontinent and has set about securing non-exclusive cooperation agreements with independent service providers for repair and maintenance.

The firm kick-started this year's 4MW onshore revolution with the launch of its 4.2MW direct-drive turbine towards the end of 2016. Most of its main rivals have since followed suit, only for Enercon to completely change tack, revealing its radical new modular approach for its 3.5MW platform in August.

The company's wide-ranging technology portfolio includes everything from the smallest EP1 (800-900kW) via the EP2 (2-2.35MW), EP3 (3.05-3.2MW), EP4 (4.2MW) and ending with the EP8 (7.58MW).

With the addition of the new modular EP3 3.5MW design, Enercon acknowledged the shift to auction systems around the world, which demand performance at a lower cost, particularly in Germany, where the company is trying to hold on to its position as market leader even as that market shrinks.

Lars Bondo Krogsgaard lasted less than two years as Nordex CEO, resigning in March after the company reduced its revenue forecasts for 2017 and 2018, which prompted a steep fall in its share price.

He was replaced by his deputy and COO, Jose Luis Blanco, former CEO of Acciona Windpower.

The news was a little more positive by the year's halfway point, with the company recording €572 million of new orders in Q2, bringing its total order backlog to €3.6 billion, including service contracts.

The service division is now expanding quickly, up 24% on 2016 levels with a turnover of over €150 million.

But there is more pain to come. In September, Blanco announced that the group was looking to cut €21 billion from its materials and operating costs, and a further €24 million in personnel costs, with the loss of 400-500 jobs across Europe, mostly in Germany.

Germany's shift to competitive tendering has created uncertainty in Nordex's domestic market, and the pure players, including Enercon and Senvion, are struggling to adapt.

"We are responding to the changes in business volume by stepping up cost discipline to support our profitability," said Blanco.

The big news on the product front was the unveiling in September of the latest development of the 3MW Delta platform, launched in 2013.

The new model — aimed at low- and medium-speed wind sites — has a nameplate capacity of 4-4.5MW and a rotor diameter of 149 metres. The first prototype will be installed in autumn 2018, with full-scale production starting the following year.

The company has also been testing a 134-metre tubular steel tower with a diameter of 4.3 metres, which passes German transport restrictions.

The US-owned, German-headquarted turbine maker failed to make the 2016 top ten for installed capacity, according to FTI figures. But its cumulative capacity, international reach and turbine portfolio push it up in our rankings.

In the past 18 months the company has revealed new models for its 3MW platform, teased the development of a 10MW-plus offshore turbine, entered a raft of new markets, announced a 4.6% fall in revenues in H1 2017 and plans to cut 780 jobs, mainly at manufacturing sites in Germany. The firm is moving into two years of "transition", explained CEO Jürgen Geissinger.

The former Schaeffler chief has been the role for almost two years. In that time the firm has entered six new markets with supply deals in Croatia, Chile, Norway, Ireland, Serbia, and Italy (offshore), plus a troubled re-entry to India following its sale from previous owner Suzlon to Centerbridge Partners in 2015.

Senvion's onshore portfolio ranges from its MM 2-2.05MW series, of which the MM92 is its bestseller, to the 3.7M144 that was unveiled at Husum in September This turbine has already been specified for a 429MW project in Australia.

A wholly owned subsidiary of the China Guodian Corporation, one of the country's five largest state-owned power generators, United Power has felt the effects of the slowdown in wind installations in China.

According to FTI, United Power installed 3.09GW of new capacity in 2015, all of it in China, for a 4.9% share of the global market. In 2016 that dropped to 2.13GW and 3.8%. It remains China's second biggest turbine manufacturer although well behind Goldwind.

Sales are concentrated on a 1.5MW turbine with an 86-metre rotor diameter, designed by German wind power consultancy Aerodyn Engineering.

European expertise has also influenced its 2MW turbine (97-metre rotor diameter) and 3MW model (120 metres). A prototype 6MW offshore turbine with a rotor diameter of 136 metres was unveiled several years ago, but United Power did no offshore business in 2016.

Envision’s 1.5MW turbine with a 93-metre rotor diameter
Envision has been exploring new markets and new technologies to compensate for the slowdown in China. It installed just over 2GW in 2016, mostly at home, but it won a 90MW deal in Mexico and has signed contracts for 185MW of projects in Argentina.

The firm acquired the French onshore wind portfolio of European developer Velocita Energy Developments, which includes a 500MW pipeline. It has also been doing its homework in India, ahead of a possible entry into the world's fourth-largest market.

A European consortium last year selected Envision's low-wind turbines to be fitted with a direct-drive superconductor generator — a device claimed to be capable of tripling wind-power generation.

In 2016 the firm unveiled its EnSight energy analytics platform and EnOS system, which it claims can manage "all types of energy infrastructure", from wind turbines to storage devices, and smart grids to home appliances.

Technology giants have taken notice, and this year Microsoft and Accenture teamed up with Envision to develop an internet-of-things programme.

India's leading domestic turbine maker only makes to top ten on the back of its historical record and the future promise of its domestic market.

It installed 1.14GW in 2016, placing it 16th in FTI's table of leading wind turbine suppliers. But it lies eighth in terms of cumulative capacity, with 16.8GW of turbines operating in North and Latin America, Europe and Australia.

India's ambitious wind targets offer ample opportunities for growth, not least in repowering, but other manufacturers are eyeing the market, and Suzlon will have to up its game on the technological front.

Because we are from Croatia, we have to mention Croatian company KONČAR.

Wind Turbines made by KONČAR are completely automatized wind turbines. They are initialled when the wind speed reaches the power designed for their start-up. The wind turbine output power raises with the speed of the wind. Wind turbines reach their nominal power at a certain wind velocity (depending on the wind turbine type).

When the wind reaches a speed for which the wind turbine is designed to stop working, blades start to rotate on their axes until they obtain the position in which they put up the lowest resistance to the wind and the wind turbine is under the so-called free-wheeling condition, the condition of free rotation.

The nacelle is equipped with a yaw system, turning the nacelle always towards the wind. All nacelle components are installed in a line related to the wind turbine main axis. Besides the nacelle yaw system, the wind turbine also has a generator excitement system, control system, lubrication system, braking system, blade turning system, fire alarming system and a nacelle air-conditioning and heating system.

The direct wind turbine operation solution (without a gearbox) has several benefits compared to other possible solutions. Such turbines use more wind power by 10-15 % transforming it into the electric power, decrease mechanical losses and the level of noise, achieve higher operational safety and it is also worthwhile to mention the benefit of a simpler maintenance of those wind turbines.

Zeljko Serdar,
Croatian Center of Renewable Energy Sources (CCRES)

ponedjeljak, 18. prosinca 2017.

Renewable Energy Industry Outlook

Renewable Energy Industry Outlook

The renewable electricity market has witnessed an unprecedented acceleration in recent years, and it broke another annual deployment record in 2017. The market’s main driver last year was solar photovoltaics, which is boosting the growth of renewables in power capacity around the world. As costs decline, wind and solar are becoming increasingly comparable to new-build fossil fuel alternatives in a growing number of countries. China remains the dominant player, but India is increasingly moving to the centre stage. Government policies are introducing more competition through renewable auctions, further reducing costs.

Solar energy
Solar energy is the conversion of sunlight into usable energy forms. Solar photovoltaics (PV), solar thermal electricity and solar heating and cooling are well established solar technologies.

Solar photovoltaics
Solar photovoltaic (PV) systems directly convert solar energy into electricity. Solar PV combines two advantages. On the one hand, module manufacturing can be done in large plants, which allows for economies of scale. On the other hand, PV is a very modular technology. It can be deployed in very small quantities at a time. This quality allows for a wide range of applications. Systems can be very small, such as in calculators or off-grid applications, up to utility-scale power generation facilities.

In 2017, cumulative solar PV capacity reached almost 300 GW and generated over 310 TWh, 26% higher than in 2015 and representing just over 1% of global power output. Utility-scale projects account for 55% of total PV installed capacity, with the rest in distributed applications (residential, commercial and off-grid). Over the next five years, solar PV is expected to lead renewable electricity capacity growth, expanding by almost 440 GW under the Renewables 2017 main case.  

As PV generates power from sunlight, power output is limited to times when the sun is shining. However, as the IEA’s analysis on the system integration of variable renewable renewables has highlighted, a number of options (demand response, flexible generation, grid infrastructure, storage) exist to cost-effectively deal with this challenge.

Concentrating solar power
Concentrating solar power (CSP) devices concentrate energy from the sun’s rays to heat a receiver to high temperatures. This heat is then transformed into electricity – solar thermal electricity (STE).

From a system perspective, STE offers significant advantages over PV, mostly because of its built-in thermal storage capabilities. CSP plants can continue to produce electricity even when clouds block the sun, or after sundown or in early morning when power demand steps up. Both technologies, while being competitors on some projects, are ultimately complementary.

The deployment of CSP plants is at a stage of market introduction and expansion. In 2016, the installed capacity of CSP worldwide was 4.8 GW, compared to 300 GW of solar PV capacity.  CSP capacity is expected to double by 2022 and reach 10 GW with almost all new capacity incorporating storage. CSP with storage can increase the flexibility of an energy system, facilitating the integration of variable renewable technologies such as solar PV and wind.

Solar heating and cooling
Solar thermal technologies can produce heat for hot water, space heating and industrial processes, with systems ranging from small residential scale to very large community and industrial scale. The required temperature to meet the heat demand determines the collector type and design.

Cumulative installed capacity of solar thermal installations reached an estimated 456 GWth by the end of 2017. However, the market continued to slow in 2017 for the third year in a row, as total annual installations decreased by 9% owing mainly to a continual slowdown in China.

To 2022, solar thermal heat consumption is expected to grow by over one-third, with installations in the buildings sector driving most of the increase. In the growing global market for cooling, there is also a huge potential for cooling systems that use solar thermal energy. By the end of 2016, an estimated 1,350 solar cooling systems were in operation globally.

Wind energy
Wind energy is developing towards a mainstream, competitive and reliable power technology. Globally, progress continues to be strong, with more active countries and players, and rapidly increasing installed capacity and investments.

Technology improvements (such as larger turbines) have continuously reduced costs, with some particularly impressive cost reductions for offshore wind in recent years. The industry has overcome supply bottlenecks and expanded supply chains.

Wind-generated electricity met close to 4% of the world’s electricity demand in 2015—a record-setting year with more than 63 GW of new wind power capacity installed. The global wind energy potential is vast: wind could account for up to 30% of global power generation by 2040, according to the World Energy Outlook 2016.

Like with solar PV, the output from wind power is variable. However, countries like Denmark, which already has a wind share of around 40% of electricity production, have demonstrated that this variability can be dealt with through appropriate system operation and market design measures.

Onshore wind is a proven, mature technology with an extensive global supply chain. Onshore technology has evolved over the last five years to maximise electricity produced per megawatt capacity installed to unlock more sites with lower wind speeds. Machines have become bigger with taller hub heights, larger rotor diameters and in some cases bigger generators depending on the wind and site-specific conditions.

Onshore wind leads global renewable energy growth, accounting for over one-third of the renewable capacity and generation increase in 2015. Onshore wind generation is expected to almost double by 2021 and reach 1545 TWh.

Deploying turbines in the sea takes advantage of better wind resources than at land-based sites. Offshore turbines, therefore, achieve significantly more full-load hours.

Furthermore, offshore wind farms can be located near large coastal demand centres, often avoiding long transmission lines to get power to demand, as can be the case for land-based renewable power installations. This can make offshore particularly attractive for countries with coastal demand areas and land-based resources located far inland, such as China, several European countries and the US.

While needing to satisfy environmental stakeholders, offshore wind farms generally face less public opposition and, to date, less competition for space compared with developments on land. As a result, projects can be large, with the 630 MW London Array wind farm currently being the largest in the world.

In 2015, global offshore wind generation reached an estimated 38 TWh, 50% higher than in 2014. At the end of 2015, global offshore wind cumulative capacity was 12 GW, and this is expected to triple by 2021.

The expansion of offshore wind is being helped by rapid costs reductions thanks to competitive auctions and larger turbines sizes. In late 2016, the winning bid for the Borssele III and IV Wind Farms in the Netherlands reached a new record low cost of €55/MWh.

Ocean energy
Ocean power accounts for the smallest portion of renewable electricity globally, and the majority of projects remain at the demonstration phase. However, with large, well-distributed resources, ocean energy has the potential to scale up over the long term.

Five different ocean energy technologies are under development:

Tidal power: the potential energy associated with tides can be harnessed by building a barrage or other forms of construction across an estuary.
Tidal (marine) currents: the kinetic energy associated with tidal (marine) currents can be harnessed using modular systems.
Wave power: the kinetic and potential energy associated with ocean waves can be harnessed by a range of technologies under development.
Temperature gradients: the temperature gradient between the sea surface and deep water can be harnessed using different ocean thermal energy conversion (OTEC) processes.
Salinity gradients: at the mouth of rivers, where freshwater mixes with saltwater, energy associated with the salinity gradient can be harnessed using the pressure-retarded reverse osmosis process and associated conversion technologies.
Tidal projects produce variable, but highly predictable, energy flows. Generation from wave power is variable, depending on the state of the sea.

None of these technologies is widely deployed as yet. The engineering challenges associated with efficiently intercepting energy from wave or tidal power are significant, particularly given the need to survive and operate in difficult conditions. Other issues that need to be considered include impacts on marine life, the marine environment and other marine users such as shipping, fishing industry, etc.

Tidal barrages are most advanced as they use conventional technology. However,  only two large-scale systems are in operation worldwide; the 240 MW La Rance barrage in France has been generating power since 1966, while the 254 MW Sihwa barrage (South Korea) came into operation in  2011. Other smaller projects have been commissioned in China, Canada and Russia.

For other ocean technologies, design concepts are still being researched but the leading ones have now reached the point where megawatt scale installations are being demonstrated. The largest demonstration project is the 6 MW MeyGen tidal array in Scotland.

Bioenergy and biofuels
Bioenergy accounts for roughly 9% of world total primary energy supply today. Over half of this relates to the traditional use of biomass in developing countries for cooking and heating, using inefficient open fires or simple cookstoves with impacts on health (e.g. due to indoor smoke pollution) and the environment.

Modern bioenergy on the other hand is an important source of renewable energy, its contribution to final energy demand across all sectors is five times higher than wind and solar PV combined, even when the traditional use of biomass is excluded. Around 13 EJ of bioenergy was consumed in 2015 to provide heat, representing around 6% of global heat consumption. In recent years, bioenergy for electricity and transport biofuels has been growing fastest, mainly due to higher levels of policy support.

Within the industry sector, bioenergy use is common in industries which produce biomass residues on site, such as the pulp and paper industry, as well as the food processing sector, where it provides low- and medium-temperature process heat. Modern bioenergy is also widely used for space and water heating, either directly in buildings or in district heating schemes. Furthermore, around 500 TWh of electricity was generated from biomass in 2016, accounting for 2% of world electricity generation.

Liquid biofuels can be used to decarbonise the transport sector, which is still more than 90% dependent on oil. In 2017, transport biofuels provided 4% of world road transport fuel demand, with the United States and Brazil the largest producers. Biofuel production is expected to rise to 159 billion litres in five years’ time.

In the long-term bioenergy has an essential role to play in a low-carbon energy system. For instance, modern bioenergy in final global energy consumption increases four-fold by 2060 in the IEA's 2°C scenario (2DS), which seeks to limit global average temperatures from rising more than 2°C by 2100 to avoid some of the worst effects of climate change. Within this scenario it plays a particularly important role in the transport sector, where it helps to decarbonise long-haul transport (aviation, marine and long-haul road freight).

Sustainability of bioenergy supply chains is an important consideration and strong governance frameworks are needed to ensure that bioenergy use provides environmental and social benefits. As such there is growing recognition that only bioenergy supplied and used in a sustainable manner can play a role in a low carbon energy future.


Biomass: any organic matter, i.e. biological material, available on a renewable basis. Includes feedstock derived from animals or plants, such as wood and agricultural crops, and organic waste from municipal and industrial sources.
Bioenergy: energy generated from the conversion of solid, liquid and gaseous products derived from biomass.
Traditional use of solid biomass: The traditional use of solid biomass refers to the use of solid biomass with basic technologies, such as a three-stone fire, often with no or poorly operating chimneys.

Geothermal energy
Geothermal energy can provide heating, cooling and base-load power generation from high-temperature hydrothermal resources, deep aquifer systems with low and medium temperatures, and hot rock resources.

Geothermal heat is primarily used for bathing, swimming and space heating. Use in agriculture, especially for heating greenhouses, is significant in some countries. For example, in Turkey agriculture accounts for 30% of geothermal direct use. Geothermal heat uses are often small-scale and two countries (China and Turkey) account for almost 80% of global geothermal heat use.

Over the next five years, the biggest growth is expected in China, where geothermal district heating is expanding rapidly in a number of Northern cities to help tackle air pollution problems. In Europe, the use of geothermal heat in district heating is also growing, with the main markets in France, Netherlands, Germany, and Hungary.

Geothermal power plants are particularly common in countries that have high-termperature geothermal resources. In 2015, global geothermal power generation stood at an estimated 82 TWh, while the cumulative capacity reached over 13 GW. Global geothermal power capacity is expected to rise to almost 17 GW by 2021, with the biggest capacity additions expected in Indonesia, Turkey, the Philippines and Mexico.

Hydropower  is the largest source of renewable power in the world, producing around 17% of the world’s electricity. Its growth has slowed in recent years but capacity additions are expected to continue and add 135 GW by 2021.

China has driven global hydropwer growth over the last decade, with an almost tripling of hydropower generation from 2005 to 2015. The world’s largest power station, the 22.5 GW Three Gorges Dam in China, was completed in 2008. Over the next five year’s China’s role in the global market is likely to decline.

Hydropower is a mature technology, yet it continues to evolve. There has been increasing focus on the role it can play in providing system flexibility and stability, respecially where the share of variable renewables – primarily wind power and solar photovoltaic (PV) – is increasing rapidly. Reservoir hydropower plants and pump storage plants are particularly suited to providing system flexibility, while run-of-the river hydropower plants are themselves variable according to current or seasonal weather conditions.

Run-of-river hydropower plants harness energy for electricity production mainly from the available flow of the river. These plants may include short-term storage or “pondage”, allowing for some hourly or daily flexibility but they usually have substantial seasonal and yearly variations.
Reservoir hydropower plants rely on stored water in a reservoir. This provides the flexibility to generate electricity on demand and reduces dependence on the variability of inflows. Very large reservoirs can retain months or even years of average inflows and can also provide flood protection and irrigation services.
Pumped storage plants (PSPs) use water that is pumped from a lower reservoir into an upper reservoir when electricity supply exceeds demand or can be generated at low cost. When demand exceeds instantaneous electricity generation and electricity has a high value, water is released to flow back from the upper reservoir through turbines to generate electricity. Pumped storage currently represents 99% of on-grid electricity storage.

To put these issues in perspective, the most potentially impactful policies have not yet been finalized. And despite short-term uncertainty, renewable power sources are riding some very strong tailwinds that will likely continue to promote growth in the longer term.

petak, 8. prosinca 2017.


Agronomic values of biochar

The needs to develop more sustainable agriculture systems and improve weak rural economies necessitate major changes in agriculture management. Soil degradation, including decreased fertility and increased erosion, is a major concern in agriculture. Long term cultivation of soils could result in degradation, containing soil acidification, soil organic matter depletion, and severe soil erosion. Furthermore, the decrease in soil organic matter decreases the aggregate stability of soil, therefore, it is crucial to remediate the degradation soils by simple and sustainable methods.

The thermal process that produces biochar is called pyrolysis, pyro, meaning fire and lysis, meaning separation. During pyrolysis, the crucial trace elements found in plants (over 50 metals) become part of the carbon structure, thereby preventing them from being leached out while making them available to plants via root exudates and microbial symbiosis.
A range of organic chemicals are produced during pyrolysis. Some of these remain stuck to the pores and surfaces of the biochar and may have a role in stimulating a plant’s internal immune system, thereby increasing its resistance to pathogens. The effect on plant defense mechanisms was mainly observed when using low temperature biochars.This potential use is, however, only just now being developed and still requires a lot of research effort.

Soil mineral depletion is a major issue due mainly to soil erosion and nutrient leaching. The addition of biochar is a solution because biochar has been shown to improve soil fertility, to promote plant growth, to increase crop yield, and to reduce contaminations. We review here biochar potential to improve soil fertility. The main properties of biochar are the following: high surface area with many functional groups, high nutrient content, and slow-release fertilizer.

Biochar is much too valuable for it to be just added to soil without using it at least once for other beneficial purposes. Basic uses include: drinking water filtration, sanitation of human and kitchen wastes, and as a composting agent. All of these uses have been documented in many different pre-industrial cultures. In the modern world, the uses multiply: adsorber in functional clothing, insulation in the building industry, as carbon electrodes in capacitors for energy storage, food packaging, waste water treatment, air cleaning, silage agent or feed supplement. All those uses could be part of more complex cascades when, after extended up- and down cycling, biochar can be used in a farmer’s manure slurry pit or in a sewage treatment plant, before being composted and thus finally becoming a soil amendment. Biochar should only be worked into the soil at the end of such cascades, keeping in mind that some biochar uses, for cleaning up metal or chemical contamination, would render the biochar unsuitable for agricultural soils and need different recycling pathways.

At present some 40% of the biochar used in Croatia goes into animal farming.
Different to its application to Croatian fields, a farmer will notice its effects within a few days. Whether used in feeding, litter or in slurry treatment, a farmer will quickly notice less smell. Used as a feed supplement, the incidence of diarrhea rapidly decreases, feed intake is improved, allergies disappear, and the animals become calmer. In Germany, researchers conducted a controlled experiment in a dairy that was experiencing a number of common health problems: reduced performance, movement disorder, fertility disorders, inflammation of the urinary bladder, viscous salivas, and diarrhea. Animals were fed different combinations of charcoal, sauerkraut juice or humic acids over periods of 4 to 6 weeks. Experimenters found that oral application of charcoal (from 200 to 400 g/day), sauerkraut juice and humic acids influenced the antibody levels to C. botulinum, indicating reduced gastrointestinal neurotoxin burden. They found that when the feed supplements were ended, antibody levels increased, indicating that regular feeding of charcoal and other supplements had a tonic effect on cow health.

20% of the biochar used in Croatia goes into soil.
The application of biochar into soils has great potential for improving soils fertility and promoting plant growth. The choice of biochar managing various soils is flexible, because diverse biomass materials could be used as feedstocks of biochars and the feedstocks could be pyrolyzed at different temperatures. Moreover, biochar has huge surface area, well-developed pore structure, amounts of exchangeable cations and nutrient elements, and plenty of liming. Because of these properties, soil properties could be improved after biochar treatment. For instance, the huge surface area and well-developed pore structure may increase the water holding capacity and microbial abundance. The cation exchange capacity and availability of nutrients could be increased due to the amounts of exchangeable cations and nutrient elements. The increased pH of soils should be attributed to the plenty of liming contained in biochar. Therefore, improvements of soil physical, chemical, and biological properties promote the productivity of plant through increasing the amount of nutrient elements, enhancing availability of nutrient elements, reducing nutrient leaching, and mitigating gaseous nutrients losses.

These results of characterization analyses, column experiments and some field trials indicated that biochar could be designed or may have the potential to manage specific soil purposefully, through controlling the feedstock and pyrolysis conditions. Biochar can be a novel and feasible fertilizer directly or indirectly. This is not only because of the biochars fertility but also their environmental and economic benefits. Despite the interests of using biochars to manage soils is increasing, some studies are also reported the negative effects and a number of research gaps as well as uncertainties still exist as discussed above in this review. In order to clear these knowledge gaps, further relevant investigations are inevitable in the following research, especially long-term experiments.


Schmidt HP, Wilson K:
‘The 55 uses of biochar’
Yang Ding, Yunguo Liu:
‘Biochar to improve soil fertility’
Zeljko Serdar:
‘Agronomic values of biochar’
Aciego Pietry:
‘Relationships between soil pH and microbial properties in a UK arable soil’

Croatian Center of Renewable Energy Sources (CCRES)