PRODUCTION AND USE OF BIOGAS AT THE PIG FARM

Summary

This project deals with biomass energy utilisation at a pig farm. Currently there are 22 thousand pigs and 45 thousand hens at the farm. A main difficulty for the farm is the absence of waste management system. The owners of the farm have serious intention to improve environmental situation at this site and is seeking possibility for biogas production to reduce total energy costs.

Besides, owners have another pig farm. Their plan is to construct another biogas plant at this farm after successful construction of the first one.

A sanatorium for children with tuberculosis is located at the distance of 1 km from the farm. The sanatorium is using natural gas for energy production for hot water supply and for space heating.

Investment opportunity
The biogas can be used in an internal combustion engine driving an electric generator and also producing at the same time heat energy (CHP unit).
The main benefits associated with energy production in the CHP unit, using the biogas from the treatment of the manure, are the following: / Highlights
Expected annual production of the biogas: 2 844 000 m3
Expected annual heat energy production: 7 000MWh
Expected annual electricityproduction: 6 400MWh
  • Substitution of electricity purchased for the farm
  • Substitution of electricity consumed by other premises of the Customer (another pig farm, juice production plant, slaughter house, offices) and sale of excess electricity on the basis of direct agreements
  • Substitution of production of heat at the farm
  • Sales of excess heat to sanatorium to substitute natural gas for hot water production and for heating
  • Anticipated income from the sale of the organic fertiliser
  • Avoiding disposal cost of manure and slaughter- house wastes
  • Savings, due to prevention of environmental pollution (avoiding environmental penalties).

Average heating energy demand per season and site

Season / Units / Farm / Sanatorium
Heat energy / MWh / 1037 / 3240
Electricity / MWh / 603 / 216

Project description

Modern anaerobic digestion technology, for processing various agricultural wastes in order to produce biogas, is to be introduced at the farm. Proposed project will include installation of Biogas reactor and a CHP unit, producing electricity and heat, which will be used at the farm, the sanatorium and other sites of the company. The CHP unit has an electric capacity of 835 kWel and a thermal one of 934 kWth..

The relevant data for energy production are shown in the table next.

Annual energy data of the combined biogas – CHP plant

Parameter / Unit / Value
Gross electric energy / MWh/y / 6412,8
Gross thermal energy / MWh/y / 7173,1
Total gross energy / MWh/y / 13585,9
Overall CHP efficiency coefficient / % / 84,5
Biogas fuel input / MWh/y / 16078
Biogas consumption / 1000 m3/y / 2516,5
Available biogas / 1000 m3/y / 2844
Excess biogas / 1000 m3/y / 327,5

Savings and other benefits

The total investment costs of the Biogas reactor with the CHP unit is 1,7 mln. Euros (VAT inclusive),includingdesign, construction and mounting works. The overall savings, from the operation of the combined system of the Biogas reactor and the CHP unit, are actually from two sources:

  • The total net income,including: sales of heat to Sanatorium, sales of electricity (in case of CHP) to other sites of the companyand sales of organic fertiliser.
  • The savings from the Baseline operational conditions - avoidance of the cost for the solid fuel, the diesel fuel, electricity and the disposal of the slaughter–house wastes, manure and hen-droppings.

Savings (€) from the installation of the Biogas reactor with the CHP unit

Year / 2008 / 2009 / 2010 / 2011 / 2012 / 2013 / 2014 / 2015
Total savings (€) / 459 524 / 496 616 / 537 030 / 581 084 / 629 122 / 681 554 / 738 618 / 800 803

The alternative equipment configuration has been evaluated, also. This option is include installation of Biogas reactor and a boiler, producing heat for the farm and the sanatorium. The capacity of the selected hot water boiler is 1 MW.The total investment costs of the Biogas reactor with the boiler is 900 000 Euros (VAT inclusive), including design, construction and mounting works. The overall savings in the year 2008 from the operation of the Biogas reactor in combination with a biogas hot water boiler, are 217 334 Euros.