For measuring its performance, VSBK is compared with the common local brick kilns. While clamp kilns are still predominant in rural Afghanistan, Bull’s Trench Kiln (BTK) is the most commonly used kiln types in the urban areas. Consequently the VSBK performance is compared with BTK with fixed chimneys.

Environment Friendly:

The climate-relevant emissions of a VSBK are 85% lower, compared to a BTK. In detail: CO2 emissions are reduced by 30-50% and similarly Black Carbon, the principal cause of the Asian Brown Haze, is reduced by up to 90-96%.* Combined, one four-shaft VSBK reduces every week greenhouse gas emissions equivalent to a transatlantic flight with 200 passenger when compared to a BTK producing the same number of bricks. In addition, particulate matter, which is the main reason for deteriorating air in most South Asian cities, is reduced by 80% for a VSBK compared to a BTK. The VSBK also has a smaller footprint, protecting scarce agricultural land.

Due to the fact that a VSBK can only be fired with coal (or with coal dust), pressure on forest is decreased and toxic emissions from tyres commonly fired in clamp kilns and BTK can be eliminated.

Energy Efficient:

The VSBK technology economises on fuel consumption by 30% to 40% as compared to a BTK. The energy saving is financially significant because energy costs are almost 50% of the annual operating expenses.

Uniform quality of production:

A correctly operated VSBK produces bricks of a higher average quality than traditional brick kilns. VSBK bricks usually have higher compressive strength than traditional bricks. But colour and ring, perceived criteria of good bricks in South Asia, of VSBK bricks may initially differ from traditional bricks. But with selection of right clay and with correct production process, these differences can be mitigated.

Operating/working conditions:

VSBK significantly minimises worker’s exposure to dust and heat while operating the kilns. During unloading in BTKs, workers are exposed to excessive brick dust and ash, affecting their health considerably. VSBK reduces the unloading crews’ dust exposure by 85% and offers them a comfortable working position.

Social:

By massively decreasing the emission of particulate matter, health risks for millions of brick labours and dwellers in urban areas can be reduced and the life expectancy of the exposed population restored. Unlike other local brick kilns, a VSBK can be operated around the year, offering the workers an upgraded and permanent employment.

* the Black Carbon data are qualified estimations based on punctual measurements in Nepal and Pakistan of laboratories in Nepal and Switzerland (Carbotech) and will have to be reconfirmed by a large scale study.