Co-designing the next generation of home energy management systems with lead-users.

Home energy management systems are widely promoted as essential components of future low carbon economies. It is argued in this paper that assumptions surrounding their deployment, and the methods used to design them, emerge from discredited models of people and energy. This offers an explanation for why their field trial performance is so inconsistent. A first of a kind field trial is reported. Three eco communities took part in a comprehensive participatory design exercise as lead users. The challenge was to help users synchronise their energy use behaviours with the availability of locally generated renewable energy sources. To meet this aim, a set of highly novel Home Energy Management interfaces were co-designed and tested. Not only were the designs radically different to the norm, but they also yielded sustained user engagement over a six-month follow-up period. It is argued that user-centred design holds the key to unlocking the energy saving potential of new domestic technologies, and this study represents a bold step in that direction.

Extent and degree of shoreline oiling: Deepwater Horizon oil spill, Gulf of Mexico, USA.

The oil from the 2010 Deepwater Horizon spill in the Gulf of Mexico was documented by shoreline assessment teams as stranding on 1,773 km of shoreline. Beaches comprised 50.8%, marshes 44.9%, and other shoreline types 4.3% of the oiled shoreline. Shoreline cleanup activities were authorized on 660 km, or 73.3% of oiled beaches and up to 71 km, or 8.9% of oiled marshes and associated habitats. One year after the spill began, oil remained on 847 km; two years later, oil remained on 687 km, though at much lesser degrees of oiling. For example, shorelines characterized as heavily oiled went from a maximum of 360 km, to 22.4 km one year later, and to 6.4 km two years later. Shoreline cleanup has been conducted to meet habitat-specific cleanup endpoints and will continue until all oiled shoreline segments meet endpoints. The entire shoreline cleanup program has been managed under the Shoreline Cleanup Assessment Technique (SCAT) Program, which is a systematic, objective, and inclusive process to collect data on shoreline oiling conditions and support decision making on appropriate cleanup methods and endpoints. It was a particularly valuable and effective process during such a complex spill.

The persistence and character of stranded oil on coarse-sediment beaches.

Small amounts of oil that can persist for decades in the intertidal zone of coarse-sediment beaches have been documented in a few well-studied cases. Oil that survives attenuation over the short-term (weeks to months) will persist until there is a change in the environmental conditions, as might occur where there is a seasonal storm-wave climate or as a beach undergoes long-term (erosional) changes. Oil residues can persist on the beach surface as tar mats, asphalt-like pavements, or as veneers on sediment particles or hard surfaces. Subsurface oil residues can persist in similar forms or as fill or partial fill of the pore spaces between coarse-sediment particles. Oil penetrates until it reaches fine-grained sediment, the water table, bedrock, or other penetration-limiting layers. Amounts of persistent oil are very small fractions of the volumes that were originally stranded and these protected residues can continue to biodegrade as they become thinner and more discontinuous.

Interaction of oil and mineral fines on shorelines: review and assessment.

The interaction of fine mineral particles with stranded oil in an aqueous medium reduces the adhesion of the oil to solid surfaces, such as sediments or bedrock. The net result is the formation of stable, micron-sized, oil droplets that disperse into the water column. In turn, the increase in surface area makes the oil more available for biodegradation. This interaction, referred to as oil-mineral aggregate (OMA) formation, can explain how oiled shorelines are cleaned naturally in the absence of wave action in very sheltered coastal environments. OMA formation also plays an important role in the efficacy of shoreline treatment techniques, such as physical mixing and sediment relocation that move oiled sediments into the zone of wave action to promote the interaction between oil and mineral fines. Successful application of these shoreline treatment options has been demonstrated at two spill events (the Tampa Bay response in Florida and the Sea Empress operation in Wales) and at a controlled oil spill experiment in the field (the 1997 Svalbard ITOSS program). Sediment relocation harnesses the hydraulic action of waves so that the processes of fine-particle interaction and physical abrasion usually occur in tandem on open coasts. There has been no evidence of significant detrimental side-effects of residual oil in pelagic or benthic environments associated with the use of these treatment options to enhance rates of dispersion and oil biodegradation.

The development of the SCAT process for the assessment of oiled shorelines.

The Shoreline Cleanup Assessment Team (SCAT) process is a tool to assess oiled shorelines and is now an integral component of spill response operations. The key element of a SCAT survey is a systematic documentation using standard terms and definitions of the shoreline in the areas affected by an oil spill. SCAT programs were initially established to provide objective and accurate shoreline oiling information directly to cleanup operations. The role of the SCAT program has since expanded and the information generated by the field teams is used now by planners and decision-makers and to develop shoreline treatment recommendations, to select appropriate treatment techniques, and to establish the level or degree of treatment that is appropriate. This latter point is an integral part of establishing shoreline treatment criteria or standards and treatment end points.

Tar ball frequency data and analytical results from a long-term beach monitoring program.

Following the spill of fuel oils from the New Carissa in February 1999, approximately 300 km of beaches on the Pacific coast of North America were surveyed. A long-term observation program focused on the documentation of stranded tar balls in the vicinity of the spill site. Systematic beach surveys which were conducted over the period March 1999 to April 2001 and semi-logarithmic scale, time-series plots proved the most useful format for identifying trends. Beach monitoring continued through to August 2001. by which time 212 tar balls had been analyzed by GC/MS for their chemical characteristics. The samples of tar balls collected between February 1999 and August 2001 were qualitatively compared with New Carissa source oils (NCSO) and 101 (48%) were not consistent with NSCO. The presence of tar balls that are not related to an incident can confound attempts to define cleanup or endpoint criteria and to assess possible injury to natural resources.

Aqueous vapor extraction: a previously unrecognized weathering process affecting oil spills in vigorously aerated water.

Simple evaporation of spilled oil is usually thought to be restricted to the smaller hydrocarbons (<15 carbons). We show that aeration of oil in water, at 22 degrees C, substantially extends this evaporation, leading to the loss of alkanes up to at least hexatricosane (nC36) and of polycyclic aromatic hydrocarbons with at least four rings (e.g., chrysene and its alkylated forms). This phenomenon is apparently related to steam distillation and should be considered as an important candidate pathway to explain the observed weathering of oil spilled from the OSSA II pipeline into the Río Desaguadero on the Bolivian Altiplano (approximately 3700 m), which occurred during a very turbulent flood.

Weathering of an Arctic oil spill over 20 years: the BIOS experiment revisited. Baffin Island Oil Spill.

A small experimental oil spill was conducted on the northern tip of Baffin Island Nunavut, Canada (72 degrees 31' N, 79 degrees 50' W) in August 1981, and the natural weathering of the oil has been followed by periodic visits. This paper reports on the chemical composition of oil collected in August 2001. The vast majority of the initial oil has gone, but small patches remain. Some samples remain essentially unaltered despite their 20 years of exposure to the elements, while others show that biodegradation and photooxidation can play important roles in removing the majority of the components of the oil. Using 17alpha(H)21beta(H)hopane as a conserved marker within the oil, we show that the most biodegraded sample has lost more than 87% of the hydrocarbons initially present, while another has lost a substantial proportion of its initial chrysene and alkylated congeners. Potential explanations for the different weathering patterns seen in samples collected from this small site are briefly discussed.