Tom Dolan

Financial appraisal of wet mesophilic AD technology as a renewable energy and waste management technology.

Anaerobic digestion (AD) has the potential to support diversion of organic waste from landfill and increase renewable energy production. However, diffusion of this technology has been uneven, with countries such as Germany and Sweden taking the lead, but limited diffusion in other countries such as the UK. In this context, this study explores the financial viability of AD in the UK to offer reasons why it has not been more widely used. This paper presents a model that calculates the Internal Rate of Return (IRR) on a twenty year investment in a 30,000 tonnes per annum wet mesophilic AD plant in the UK for the treatment of source separated organic waste, which is judged to be a suitable technology for the UK climate. The model evaluates the financial significance of the different alternative energy outputs from this AD plant and the resulting economic subsidies paid for renewable energy. Results show that renewable electricity and renewable heat sales supported by renewable electricity and renewable heat tariffs generates the greatest IRR (31.26%). All other uses of biogas generate an IRR in excess of 15%, and are judged to be a financially viable investment. Sensitivity analysis highlights the financial significance of: economic incentive payments and a waste management gate fee; and demonstrates that the fate of the digestate by-product is a source of financial uncertainty for AD investors.

Is the EU drinking water directive standard for pesticides in drinking water consistent with the precautionary principle

Regulations based on the precautionary principle should undertake a comprehensive assessment of all available scientific and technical data to identify sources of epistemic uncertainty. In the European Union (EU), environmental regulation is required to fulfill the principles established in Article 174 of the EU Treaty, such that it offers a high level of protection and is consistent with the precautionary principle. Pesticides in drinking water are currently regulated by the Drinking Water Directive using a maximum allowable concentration of 0.1 μg/L. This standard (a surrogate zero) was consistent with the precautionary principle when it was originally set in 1980 and remained consistent when retained in 1998. However, given developments in EU pesticide and water policy, international experience in regulating pesticides, and an increasing knowledge of pesticide toxicity, it can be argued that the level of epistemic uncertainty faced by regulators has substantially decreased. In this paper, we examine the extent to which such developments now challenge the basis of European drinking water standards for pesticides and whether, for substances for which there is good toxicological understanding, a regulatory approach based upon the World Health Organization (WHO) Guideline Value (GV) methodology would be more consistent with the principles underpinning European environmental policy.

Identifying Adaptation Options and Constraints: The Role of Agronomist Knowledge in Catchment Management Strategy

Water suppliers in parts of Europe currently face occasional Drinking Water Directive compliance challenges for a number of pesticide active substances including metaldehyde, clopyralid and propyzamide. Water Framework Directive (WFD) Article 7 promotes a prevention-led (catchment management) approach to such issues. At the same time, European pesticide legislation is driving reduced active substance availability. In this context, embedding agronomic drivers of pesticide use into catchment management and regulatory decision making processes can help to ensure that water quality problems are addressed at source without imposition of disproportionate cost on either agriculture or potable water suppliers. In this study agronomist knowledge, perception and expectations of current and possible future pesticide use was assessed and the significance of this knowledge to other stakeholders involved with pesticide catchment management was evaluated. This was then used to provide insight into the possible impacts of active substance restrictions and associated adaptation options. For many arable crops, further restrictions on the range of pesticides available may cause increased use of alternatives (with potential for “pollution swapping”). However, in many cases alternatives are not available, too costly or lack a proven track record and other adaptation options may be selected which catchment managers need to be able to anticipate.