Browsing by Author "Lord, Richard"

Now showing 1 - 2 of 2
  • Thumbnail Image
    ItemOpen Access
    A framework for reviewing the trade-offs between, renewable energy, food, feed and wood production at a local level
    (Pergamon, 2012-01-31T00:00:00Z) Burgess, Paul J.; Rivas Casado, Monica; Gavu, Jerry; Mead, Andrew; Cockerill, Tim; Lord, Richard; van der Horst, Dan; Howard, David C.
    High fuel prices and concerns about energy security and anthropogenic climate change are encouraging a transition towards a low carbon economy. Although energy policy is typically set at a national level, tools are needed for people to engage with energy policy at regional and local levels, and to guide decisions regarding land use, distributed generation and energy supply and demand. The aim of this paper is to develop a per-capita approach to renewable energy demand and supply within a landscape and to illustrate the key trade-offs between renewable energy, food, (animal) feed and wood production. The chosen case study area (16,000 ha) of Marston Vale, England is anticipated to have a population density midway between that for England and the UK. The daily per capita demand for energy for heat (31 kWh), transport (34 kWh) and electricity (15 kWh) when combined (80 kWh) was seven-fold higher than the combined demand for food (2 kWh), animal feed (6 kWh), and wood (4 kWh). Using described algorithms, the combined potential energy supply from domestic wind and photovoltaic panels, solar heating, ground-source heat, and municipal waste was limited (<10 kWh p−1d−1). Additional electricity could be generated from landfill gas and commercial wind turbines, but these have temporal implications. Using a geographical information system and the Yield-SAFE tree and crop yield model, the capacity to supply bioethanol, biodiesel, and biomass, food, feed and wood was calculated and illustrated for three land-use scenarios. These scenarios highlight the limits on meeting energy demands for transport (33%) and heat (53%), even if all of the arable and grassland area was planted to a high yielding crop like wheat. The described framework therefore highlights the major constraints faced in meeting current UK energy demands from land-based renewable energy and the stark choices faced by decision mak
  • Thumbnail Image
    ItemOpen Access
    Ten-year legacy of organic carbon in non-agricultural (brownfield) soils restored using green waste compost exceeds 4 per mille per annum: Benefits and trade-offs of a circular economy approach
    (Elsevier, 2019-06-24) Lord, Richard; Sakrabani, Ruben
    Soil organic carbon (SOC) was re-analysed 10 years after application of source-segregated green waste compost at a 1 ha previously-developed UK site to compare with the increases suggested by the 4 per mille initiative proposed at COP21 in Paris. Compost prepared to PAS100 standard had been incorporated once at rates of 250, 500 and 750 t·ha−1 in 2007 in clay subsoil prior to planting of perennial energy crops. Our results show statistically significant differential increases in SOC, total nutrients N and P, or contaminants Zn, Pb, Cu, As and B, remain from the compost application after a decade. For the 500 or 750 t·ha−1 compost rates the SOC increments in the upper 10–15 cm were 0.85% or 1.6% over the 4.9% developed from a baseline of 1.8% in control areas by a decade of natural regeneration. Calculation of the elemental loadings from the compost analyses compared to the present-day levels suggests SOC declines after application at an average annual rate approaching 10%, compared to 5% for the nutrients or contaminants, roughly equivalent to half-lives of 5 or 10 years respectively. The study demonstrates the long-term soil organic matter (SOM) additions, fertility benefits and technical feasibility of a one-off, high-rate application of waste-derived compost to improve urban soils, compared to the potential trade-off of adding to PTE loadings. This longevity of SOC addition, previously unrecognised in brownfield soils, may be inferred for other areas where further cultivation is precluded, as is typical after landscape restoration or under perennial energy crops for the production of biomass. This unprecedented result has wider implications for marginal land use for bioenergy and the opportunities therein for SOC management using anthropogenic organic wastes to mitigate greenhouse gas emissions.