**1. Introduction**

180 Sustainable Growth and Applications in Renewable Energy Sources

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Committee Recommended practice for the calculation of daylight availability.

*Salix viminalis* (Common Osier, Basket Willow, Energetic Willow) is a plant belonging to the SRWC group (Short Rotation Woody Crops) (Borjesson et al., 1994; Christersson & Sennerby-Forsse, 1994). Such a qualification points out possible applications resulting from a fast growth and annual yield of biomass. The woody stems of *Salix viminalis* can be cut frequently and serve as burnable biomass. Therefore *Salix viminalis* wood is often called a "green fuel". In general, willows (genus *Salix*) are popular plants since more than 400 species occur in Nature (including *Salix viminalis*). Particularly, Northern Hemisphere is a natural region for different willow species bearing sometimes traditional and very unique names like Sageleaf Willow, Goat Willow, Pussy Willow, Coastal Plain Willow, Kimura, Grey Willow, Sand Dune Willow, Furry Willow, Heartleaf Willow, Del Norte Willow, American Willow, Drummond's Willow, Eastwood's Willow, Mountain Willow, Sierra Willow etc. The variety of willow species partly results from ease of hybrid formation by cross-fertile of particular *Salix* genotypes in a natural process and/or by planned cultivation. Table 1 contains systematic botanic classification of willows.


Table 1. Botanic classification.

The differences between *Salix* species also consists in the morphology of willows i. e. scrubs and trees naturally occur. In practice moist soils and mild climate conditions suits perfectly the demands of willows.

Energetic Willow (*Salix viminalis*) – Unconventional Applications 183

LPG ca. 45

Dry straw ca. 15

Table 3. Heat of combustion of selected fuels. The content of the table selected from the

Table 4**.** Dry biomass prices in Poland. The content of the table selected from the original

Thus, 1000 kg of dry *Salix viminalis* wood offers amount of energy comparable to 700 kg of black coal of good quality. However, black coal mining is evidently associated with serious irreversible environmental damages what becomes more and more important issue nowadays. This is a next argument for increasing of biomass production and usage for energetic purposes. Energetic utilization of other plants from SRWC group like *Plantanus occidentalis, Liquidambar styraciflua, Pennisetum purpureum, Erianthus arundenaceum, Panicum virgatum, Ricinus communis, Hibiscus cannabinnis, Populus deltoids, Pinus elliottii, EucaIypytus amplifolis, Eucalyptus grandis,* or *Pinus taeda* is a much more rare case in the world scale and particularly in Europe where climate conditions are often the main limiting factor. In Europe, *Salix viminalis* wood seen as renewable source of "green fuel" has a one important competitor i. e. dry straw. Straw is a side product (ca. 20 billion kg per annum in Poland) of grains cultivation i. e. one of the most frequent agricultural

Phytoremediation of soil and waters is a task of numerous research projects and technological undertakings. Such attempts base on an unique feature of *Salix viminalis* i. e. the ability to effective uptake, deactivation and accumulation of relatively high amounts of

Fuel oil (light fraction) ca. 42 Fuel oil (heavy fraction) ca. 40 Black coal ca. 27 Coke ca. 25

Dry wood (incl. Energetic Willow) ca. 19

frequency\*

original material and translated (Iso-Tech, 2011).

Plant Plantation no. Harvest

\*Harvest frequency: 1 – each year, 2 - every 2 years, 3 – every 3 years

Energetic

Energetic

Willow <sup>8</sup>

Willow <sup>9</sup>

activities (Gradziuk, 1999).

**2.2 Environment protection - Phytoremediation** 

\*\*PLN – currency of Poland, 1 EUR = 4 PLN Source: http://www.bio-energia.pl/

source and translated (Bio-energia, 2008).

Fuel Heat of combustion [GJ/1000 kg]

Dry biomass price

Brutto [PLN\*\* / 1000 kg]

Netto [PLN\*\* / 1000 kg]

1 367 491 2 333 458 3 253 356

1 346 447 2 335 444 3 247 337
