Martin Anda

Constructed wetlands have gained increasing international recognition as passive, low-energy alternatives to conventional wastewater treatment infrastructure. Despite decades of global research, application in remote and community-scale contexts across Australia and Southeast Asia remains limited. Many remote Australian Aboriginal communities and rural Southeast Asian villages are in urgent need of improved and sustainable wastewater management, yet lack access to systems that are affordable, locally maintainable, and adapted to their specific environmental and social conditions. This paper synthesises the findings of a 30-year constructed wetland research program at Murdoch University, Perth, Western Australia, reviewing doctoral theses, honours projects and peer-reviewed publications spanning domestic greywater, industrial effluent, community-scale water recycling, oilfield produced water, stormwater management and urban biophilic design. Technology readiness is assessed using the Technology Readiness Level (TRL) framework, and a structured knowledge gap analysis identifies the prerequisites for achieving TRL 6 — system demonstration in a relevant operational environment — across a broader context of remote Australian communities and rural Southeast Asian villages. Two specific demonstration sites are proposed: a remote Aboriginal community near Geraldton, Western Australia (French two-stage vertical flow constructed wetland) to replace aging, overloaded sewage lagoons, and the Tanjung Ringgit ecovillage in East Lombok, Indonesia, where a horizontal subsurface flow (HSSF) system with upstream settling tank is proposed for maximum maintenance simplicity.

Mine tailings present a growing global environmental and economic challenge requiring integrated technological, regulatory, and circular economy responses. This review examines international trends in tailings management, with particular focus on Western Australia, drawing on comparative evidence from Brazil, Chile, South Africa, Canada, and Finland. It analyses digital innovations (AI, IoT, blockchain, UAVs) alongside circular economy strategies, evaluates regulatory frameworks, and identifies key research gaps in economic assessment, long-term environmental monitoring, technological integration, and community engagement. Western Australia is identified as well-positioned to lead responsible tailings management, with lessons applicable across the global mining sector.

This study presents a three-dimensional numerical investigation of wave transmission over submerged breakwaters, with a focus on elucidating the role of structural permeability in wave energy dissipation. High-resolution simulations were conducted using FLOW-3D and rigorously validated against laboratory measurements reported by van Gent et al. (2023). The results show that permeable submerged breakwaters consistently yield lower wave transmission coefficients than impermeable configurations due to enhanced internal turbulence and porous-flow energy dissipation mechanisms. Building on the validated numerical database, a refined empirical wave transmission model is developed. Compared to the widely used formulation of van Gent et al. (2023), the proposed model reduces the root mean square error from approximately 0.045 to 0.022 while maintaining a high coefficient of determination (R² = 0.96). The improvement is most pronounced for moderate to high relative freeboard conditions, where existing models tend to underestimate transmission. A comprehensive parametric analysis further quantifies the influence of crest width, relative freeboard, and porosity on transmission behavior. The key scientific contribution of this study lies in establishing a validated numerical–empirical framework that explicitly captures three-dimensional turbulence–porosity interactions, enabling faster and more accurate prediction of wave transmission and providing a scalable alternative to extensive physical modeling for the design of submerged and reef-type breakwaters.

Murdoch University (MU) is committed to achieving net-zero Scope 1 and Scope 2 emissions by 2030. MU’s security, transport, and logistics fleet currently relies on petrol and diesel vehicles, with typical emission factors of approximately 3.2 kg CO₂-e per litre of petrol and 3.7 kg CO₂-e per litre of diesel. The fleet contributes an estimated 250–280 tCO₂-e annually, representing around 13% of MU’s Scope 1 emissions. This study presents a techno-economic evaluation of producing green hydrogen locally (on campus) for use as a direct fuel to transition MU’s fleet to hydrogen fuel cell electric vehicles (FCEVs). Two renewable electricity (RE) supply configurations were assessed for hydrogen production: a grid-connected solar PV-only option and a stand-alone hybrid solar–wind option. The results indicate that the hybrid configuration offers the most favourable feasibility and fuel-cost performance; however, the outcome is sensitive to the sell-back price for excess electricity exported to the MU campus and/or the grid. The hydrogen production, storage, and dispensing infrastructure was modelled using both (i) a discrete-component balance-of-plant (BoP) approach and (ii) a pre-engineered compact hydrogen fuelling solution, exemplified by a Simple Fuel Unit (SFU), to assess plausible upfront costs. The levelised cost of hydrogen (LCOH) was benchmarked against petrol and diesel on an equivalent cost per 100 km range basis. Under suitable excess RE sell-back arrangements, locally produced green hydrogen can deliver zero-emissions refuelling and reduce fleet fuel costs by up to 79%. The analysis also finds that FCEV leasing costs are typically 25–40% higher than comparable internal-combustion vehicles. Nevertheless, when fuel-cost savings are combined with internalised benefits, such as emissions reduction, reputational value, and potential carbon-pricing exposure, FCEV leasing can become cost-effective for MU.t Body]

The global transition to low-carbon technologies has significantly increased demand for critical minerals such as lithium, nickel, cobalt and rare earth elements. They are required for the renewable energy systems, batteries and digital Infrastructure. As the global economies move to decarbonisation, the demand for these critical minerals is increasing rapidly. Mining and mineral processing industries generate a significant amount of waste materials during the extraction of valuable minerals. These waste materials and residues are disposed of in large ponds or landfills known as Tailings Storage Facilities (TSF). These tailings residues can create significant environmental damage if not handled properly with a view to the future. At the same time, carbon emission due the increased building construction and unchecked industrial practices has become an important issue to be addressed. Implementing sustainable practices has become very urgent than ever before. Cement, a primary component of concrete, is the single largest source of carbon emissions globally, during its production contributing around 7-8% of total emissions. One ton of Ordinary Portland cement produces about 0.8 to 0.9 tons of CO2 emissions which results in it being the world’s single largest source of carbon emissions. A sustainable alternative solution to Ordinary Portland Cement in construction is Geopolymer Cement which significantly produces lower carbon emission compared to OPC. As it was found that GPC can be produced using various industrial by-products and critical minerals tailings, which makes it a sustainable option for producing low-carbon cement for the construction industry with a lower carbon emission of 80% (relative to OPC)[30]. This paper is developed with view of a comprehensive database will need to be developed for critical mineral tailings to support low carbon concrete production from geopolymer cement and promote circular economy. The establishment of a comprehensive database of mine tailings is essential for the systematic identification and utilisation of suitable tailings to produce low carbon concrete. The database will be validated with industry partners and the data provided by mining companies.

Hydrogen-based Power Systems (H2PSs) are gaining accelerating momentum globally to reduce energy costs and dependency on fossil fuels. A H2PS typically comprises three main parts: hydrogen production, storage, and power generation, called packages. A review of the literature and Original Equipment Manufacturers (OEM) datasheets reveals that no single manufacturer supplies all H2PS components, posing significant challenges in system design, parts integration, and safety assurance. Additionally, both the literature and H2PS projects’ database highlight a gap in a systematic hydrogen equipment and auxiliary sub-systems technology selection process, and how this selection affects the overall H2PS Balance of Plant (BoP). This study addresses that gap by providing a guideline for available technology options and their impact on the H2PS-BoP. The analysis compares packages and auxiliary sub-system technologies to support informed engineering decisions regarding technology and equipment selection. The study finds that each package’s technology influences the selection criteria of the other packages and the associated BoP requirements. Furthermore, the choice of technologies across packages significantly affects overall system integrity and BoP. These interdependencies are illustrated using a cause-and-effect matrix. The study’s significance lies in establishing a structured guideline for engineering design and operations, enhancing the accuracy of feasibility studies, and accelerating the global implementation of H2PS.

This study examines the embodied carbon of paving blocks by substituting Portland Composite Cement (PCC) with landfill waste incineration ash at 0%, 25%, 50%, 75%, and 100% replacement levels. Using Life Cycle Assessment (LCA) and mechanical testing, the embodied carbon value was calculated per ISO 14040 standards. Results show that a 50% replacement achieves a 33% reduction in embodied carbon (120 kgCO₂e/m³ vs. 180 kgCO₂e/m³ for conventional paving blocks) while maintaining compressive strength within SNI criteria. These findings highlight the potential for eco-cement paving blocks to support sustainable construction and inform policies promoting low-carbon building materials.