Organisation

Kilbush Nurseries produces over 1,000 tonnes of tomatoes each year. Its facilities encompass over two hectares of tomatoes under glass, in state of the art commercial greenhouse units, with integrated packing and transportation facilities. Kilbush has always striven for excellence as much in the production of its food as well as the end result and supplies high quality tomatoes to the most stringent standards set by Marks and Spencer and other reputed grocers. Varieties grown include Elegance tomatoes on the vine, Sunstream and Cocktail tomatoes.

tomatoes

This family business, now under the leadership of Matt, John and Joseph Foley, started in the 1930’s and has gone from strength to strength by innovating and anticipating trends in the market garden sector. In order to deliver a quality product competitively, the Foley family looked at ways of making their operations environmentally friendly as well as less expensive.

Keelings

The growth of Keelings has been phenomenal in more ways than one! Now expanding into Asia and with 2,000 employees, the company is still however 100% Irish owned with its roots supplying Dublin markets in the 20’s. The headquarters is at FoodCentral in Dublin, a hub of Irish food and drink producers. Key to its’ profitability is the retail and farm fresh operation as despite divergence into related areas, Keelings is still a vast producer of soft fruits, apples, vegetables and salads through its “Taste the Passion Range”.

From the 1960’s to the present day, Keelings sought innovation and state of the art techniques for their glasshouses as the business expanded to grow tomatoes, soft fruits, salad crops and traditional Irish lilies. Keelings were the first in Ireland to install CHP fuelled by natural gas in their greenhouses and reap the awards of the rise in CO2 levels made possible as a valuable by-product.

Project background

Kilbush Nurseries have been at the forefront of technical and environmental advances in the Irish horticultural sector in recent years.  And have led the way in improving the efficiency of glasshouse heating in Ireland through the use of hot water storage to meet peak heating requirements, and the installation of thermal screening to conserve energy in the glasshouse heating process. Local firm Enviroeye, acting as M&E consultants on design and energy efficiency are keen protagonists of Combined Heating and Power (CHP) and this led to Edina’s involvement with the project. The prospect of reducing energy costs and emissions, the heat recovery benefits, a longer growing season, revenue from export to grid when demand on the site is low and the use of CO2 to aid plant growth are just some of the advantages to the Nurseries with additional security of supply.

The Project at Kilbush

The installation of a TCG2020V16 engine  was proposed. Fuelled by natural gas, the engine operates at 87% efficiency and has a thermal output of 1579 kWt and 1560 kWe.

Excess electrical power is export to the grid, contributing to green energy by displacing fossil fuels and giving an additional income to Kilbush from the green power sale.

One of the greatest advantages is the use of CO2 from the emissions. Ambient levels of CO2 are around 300 parts per million (ppm) but significant improvements to certain types of plants have been observed when levels are increased to around 1,000 ppm which can be achieved from the CHP process. This remains a safe operational level for human beings and is constantly monitored.

Raising CO2 to these levels has shown a resulting rise of a staggering 50% in photosynthesis given appropriate light levels. This leads to earlier, more prolific flowering, higher fruit yield, increased plant growth and vigour, in short, “growers should regard CO2 as a nutrient”.

In order for the CHP unit to work at its optimum, Enviroeye, Edina and Kilbush co-operated closely and sought advice from experts in the treatment of exhaust gases, Steuler who have patented the leading ECO2 Pro system.

ECO2-Pro: The system

The exhaust gases of gas engines having a capacity of up to 2 MW approx. and being installed in greenhouses to produce power and heat, are cleaned by the Steuler catalyst system in two stages. This happens in such a way that they meet the necessary systems of the horticulture. Thus, the nitrogen oxides are reduced to 95 % by adding a 40 % urea solution into the exhaust gas stream in connection with a SCR-catalyst. In a second stage, the so-called oxidation stage, ethene is reduced up to 99 %. Carbon monoxide CO reaches with an emission of < 1 ppm the detection limit.

kilbush-2

The modular design facilitates of this kind of system can be easily extended. The easy operation by means of a PC mouse as well as the continuous process display on an integrated PC monitor give all information at one glance. A built-in data acquisition system offers unlimited access to all historic monitoring data. The selection of reliable mechanical components guarantee minimum maintenance time.

Advantages

  • Many years of experience in catalyst technologies
  • Short delivery periods for complete systems
  • Efficient security system for the protection of the ECO2-PRO system, the gas engine and the greenhouse plantation
  • Consent of the Netherlands Insurance Company to Steuler’s system concept
  • Small, compact design of the catalyst housing
  • Modular system of the urea metering and monitoring/control system
  • Very quick matching of the software to possible requests of the operator
  • Minimum time involved for maintenance work
  • Reliable service
  • Remote maintenance of the system

 

The Project at Keelings 

The new system provides heat and CO2 to the greenhouse, while supplying electricity to Keelings’ site loads and exporting surplus to the national grid. This will help mitigate some of the effects of high energy and carbon tax tariffs for Keelings and provide a reliable source of energy to local homes and businesses.

The provision of energy for its operations is one of the highest overheads for producers. Studies have shown that this tends to be the third greatest expense following labour and the initial cost of plants. Following the installation of natural gas CHP, these costs are offset dramatically by the advantages in heating, lighting and export to the grid all integral in the CHP system.

The system consists of a 2 MWe MWM TCG 2020 V20 gas engine with advanced exhaust gas cleaning system and TEM engine management system. Keelings’ growing season now extends from May to December.

kilbush-3

Electrical efficiency for the engine is put at 43.7%, with extremely low emissions, says MWM. In fact, emissions are so clean that it is considered safe for operatives to continue working in the greenhouse while CO2 is added. The 1,200 – 2,000 kWe output range TCG 2020 is said to offer the ‘best electrical and thermal efficiency in its output class’ and will run on all gas types, such as natural gas, biogas, landfill gas, sewage gas, mine gas, etc.

Mainly used for CHP plants in Europe and for biogas applications worldwide, the TCG 2020K has been especially adapted to non-ISO conditions such as high altitudes or high intake air temperatures in the field of natural gas. There are more than 2,000 of these power generators with approximately 2,800,000kWe already installed around the globe. The new Keelings plant in Ireland is being maintained and serviced by Edina’s Dublin service team, based in Dublin, already responsible for 60 MW within Ireland, and for 210MW of power generation across the UK.

These systems have many tangible benefits as highlighted above, not least the continued competitive edge of the growers who have worked so hard for their leading position in the economy and reputation of the business and Ireland as quality food producers.