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Miscanthus – Effluent producers and heat users

In Article 9 we covered the ability of Miscanthus to capture nitrogen, dramatically reducing leaching. This is based partly on international research but this has been confirmed in New Zealand by Dr Jeff Brown, Senior Environmental Scientist at Fonterra with his own research.

This presents a valuable opportunity for companies that produce nitrogen-rich effluent and also use heat as part of their processing. Businesses such as breweries and meat works immediately spring to mind. They can make themselves more environmentally friendly by utilising this unique ability of Miscanthus. The opportunity is there for them to demonstrate that they are actively reducing nitrogen leaching while at the same time reducing their carbon footprint. In addition they will create a resource that can be used as boiler fuel for production of their heat.


But the benefits do not stop there. At present is almost certain that district councils have to handle the effluent from these businesses and treat it appropriately before disposing of it. Much of the nitrogen almost certainly ends up being leached into the groundwater. So there is an opportunity to work with the district council to turn something that is a cost to the environment, to the council and to the business, into an environmentally benign revenue producer for the council, with potential cost savings for the business.

How would that work? In fact it is quite simple. If the company itself were to spray irrigate the effluent directly onto an adjoining Miscanthus crop, it will benefit the Miscanthus production levels while significantly reducing nitrogen leaching. If logistics and location of the business do not allow that, the council that handles the effluent can spray irrigate the effluent onto its own Miscanthus crop, happy in the knowledge that it is not contributing to increases to nitrogen in groundwater. In both cases, from year two onwards there will be harvest of the Miscanthus that produces revenue from what until now has simply been a cost.

The benefits to the council are that they will have less effluent to treat and as well as saving on that cost they will be able to generate some revenue. They will also be reducing their carbon footprint and significantly reducing their nitrogen leaching impact. It will take some time for them to get used to this idea because they are not in the habit of receiving revenue from managing effluent.

The benefits to the companies include reduction in their heating bill – probably currently produced by burning coal – improving their carbon footprint and quite importantly improving their environmental credentials because of less nitrogen leaching from their effluent. These companies may even be able to negotiate a rates reduction with the council because of the amount of money that they will be saving the council.

So all businesses that require heat for their process and also produce nitrogen rich effluent, should not only be sitting up and taking notice but they should be seeking professional advice from people who are familiar with establishment, production and use of Miscanthus in New Zealand. At present this really means Miscanthus New Zealand Limited (MNZ), or PFS Consultants Limited (PFS). Anybody wanting to get in touch with PFS can get the contact details from MNZ. Companies such as milk factories, cheese factories, meat works and breweries are all obvious candidates and one of them has already commenced discussion with MNZ. But there are sure to be many more that fit into the scenario very well.

At the same time district councils should be also seeking qualified and experienced professional advice (MNZ or PFS again) on how this could be implemented in their district to satisfy their ratepayers’ demand for improved environmental outcomes, without increasing rates. In fact there will be potential to reduce rates once they start getting into sales of the Miscanthus product that they will be growing. An excellent detailed proposal has been independently prepared for one council to put its total treated sewage output onto a Miscanthus crop. This proposal could be supplied to other councils perhaps with a few small modifications.

If the district councils do not follow up on this, the regional councils should be carrying out the same investigations so that they can then be in a position to require the district councils to act responsibly in this manner.

MNZ is completely certain that this will begin being done very soon so the choice that New Zealand companies and councils will need to make is whether they proceed in this manner voluntarily or whether they are forced to do so by a higher authority – even, if necessary, central government.

In due course MNZ will report on how things develop in relation to all of this.

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