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Domestic heating represents the most dominant energy function in Dutch households nowadays. Using district heat from CHP (combined heat and power) by means of a NGCC (natural gas-fired combined cycle) plants is generally acknowledged as an effective option to reduce primary energy consumption for heating. However, methods to calculate energy savings from CHP differ widely. This paper compares a number of different methods, including the method from the EU CHP Directive, to estimate primary energy savings in comparison with the typically used domestic gas-fired condensing boiler. Real hourly CHP plant performance data is used. An estimation of the CO2 mitigation cost of delivering district heat to Dutch dwellings is made. We find that supplying dwellings with district heat from an NGCC-CHP saves energy, regardless of the calculation method and for a rather wide range of reference efficiencies. CO2 mitigation costs are acceptable from a social perspective (at discount rates up to 4%, excluding fuel taxes) and negative from a private perspective (at discount rates up to 10%, including fuel taxes).

Objective: BeweegKuur (Exercise Therapy) is a Dutch lifestyle programme in which participants are referred by a general practitioner (GP) to a lifestyle advisor. To support participants, regional and local alliances are established. The present study explored the successes and challenges associated with collaboration processes in local BeweegKuur alliances. Design: A qualitative explorative study. Setting: The Netherlands Institute for Sports and Physical Activity (NISB) initiated the Building BeweegKuur Alliances project to support local alliances. The BeweegKuur intervention is implemented by over 30 regional and about 150 local alliances throughout the Netherlands. Method: 12 in-depth interviews were held with coordinators of the alliances, and four focus groups were held with regional and local alliance partners. Results: Collaboration within the alliances is perceived as successful in integrating prevention and care. Challenges include the participation of sectors such as the local municipality and the sports sector, and the transition of BeweegKuur participants to local sports facilities. Conclusion: This study identifies three general conditions for successful coordinated action: (a) flexible protocols and management that allow for contextual adaptations; (b) making successes and challenges visible using facilitating methods and tools; and (c) time and funding to overcome differences of culture between different sectors, and to build trust.

AbstractAlthough canopy height has long been a focus of interest in ecology, it has remained difficult to study at large spatial scales. Recently, satellite‐borne LiDAR equipment produced the first systematic high resolution maps of vegetation height worldwide. Here we show that this new resource reveals three marked modes in tropical canopy height ~40, ~12, and ~2 m corresponding to forest, savanna, and treeless landscapes. The distribution of these modes is consistent with the often hypothesized forest‐savanna bistability and suggests that both states can be stable in areas with a mean annual precipitation between ~1,500 and ~2,000 mm. Although the canopy height states correspond largely to the much discussed tree cover states, there are differences, too. For instance, there are places with savanna‐like sparse tree cover that have a forest‐like high canopy, suggesting that rather than true savanna, those are thinned relicts of forest. This illustrates how complementary sets of remotely sensed indicators may provide increasingly sophisticated ways to study ecological phenomena at a global scale.

Escalating energy costs are an increasing concern for South Asian farmers growing rice and wheat in rotation. Millions of people in the IGP (Indo-Gangetic Plains) depend on this cropping system for food and income security. CT (conservation tillage) practices, including mechanical BP (bed planting), PTOS (power-tiller operated seeding), and ST (strip tillage), are advocated by donors and development organizations as profitable, high yielding, and energy-efficient alternatives to TT (traditional tillage). However, most studies on the EUE (energy input use efficiency) of CT originate from researcher-controlled and on-station experiments. Comparatively little information is available on the EUE of CT practices as farmers apply them in their own fields, and under their own management decisions. This research responds to this gap, and analyzes EUE of each of these three CT options, compared to TT, by surveying 328 rice-wheat farmers in north-western Bangladesh. Concentrating on wheat production, we employed a non-parametric benchmarking technique involving slack-based measures of technical efficiency, along with a fractional regression model to identify and compute the wasteful use of energy. PTOS achieved the highest EUE score (0.92), followed closely by BP and ST (both 0.91), whereas TT (0.68) was significantly (p <0.001) different and lower than the CT practices.

Coherence in Photosynthesis It is unclear how energy absorbed by pigments in antenna proteins is transferred to the central site of chemical catalysis during photosynthesis. Hildner et al. (p. 1448 ) observed coherence—prolonged persistence of a quantum mechanical phase relationship—at the single-molecule level in light-harvesting complexes from purple bacteria. The results bolster conclusions from past ensemble measurements that coherence plays a pivotal role in photosynthetic energy transfer. Hayes et al. (p. 1431 , published online 18 April) examined a series of small molecules comprised of bridged chromophores that also manifest prolonged coherence.

Rising temperatures, increasingly frequent extreme weather events and sea level rise are playing a growing role in shaping displacement, rural-urban migration, circular movements but also voluntary and forced immobilities. The debate on climate mobilities – the interplay between climate change and human mobility – is currently moving centre stage in migration studies. Migration theory, on the other hand, does not necessarily reflect sufficiently on the role of the environment in mobility patterns. Including an understanding of the complex nature of climate mobilities avoids assuming climate change related mobility as new or exceptional per se, and offers understanding of the plural, multi-causal, and political ways in which climate change and human im/mobilities intersect.

AbstractClimate change and land‐use change are two major drivers of biome shifts causing habitat and biodiversity loss. What is missing is a continental‐scale future projection of the estimated relative impacts of both drivers on biome shifts over the course of this century. Here, we provide such a projection for the biodiverse region of Latin America under four socio‐economic development scenarios. We find that across all scenarios 5–6% of the total area will undergo biome shifts that can be attributed to climate change until 2099. The relative impact of climate change on biome shifts may overtake land‐use change even under an optimistic climate scenario, if land‐use expansion is halted by the mid‐century. We suggest that constraining land‐use change and preserving the remaining natural vegetation early during this century creates opportunities to mitigate climate‐change impacts during the second half of this century. Our results may guide the evaluation of socio‐economic scenarios in terms of their potential for biome conservation under global change.

An aerodynamic shape optimization method for a horizontal axis wind turbine is developed and verified through experimentation with a laboratory-scale wind turbine. Our method is based on matching the rotor's and the coupled generator's torque. Prior to shape optimization, an initial rotor design is established with a hybrid use of Schmitz and blade element momentum theories. The experimental verification of the developed method is conducted with a small-scale wind turbine; thus, the operating Reynolds number is one order of magnitude lower than large-scale wind turbines. Therefore, a high-lift low-Re airfoil, namely, SG6043, is selected for the blade along the whole span. The shape is optimized by determining the optimum chord and cumulative pitch angle distributions by manipulating the tapering and twisting of the blade. The objective of the optimization is to maximize the turbine's power coefficient Cp, while maintaining the torque equal to that of the generator. The generator's characteristics are found through experimentations which are conducted apart from the wind tunnel experiments. During the optimization process, the local aerodynamic forces on the blade are calculated by interfacing the optimization program with XFOIL; thus, the torque and power can be calculated for the rotor at each iteration step. The optimized turbine performance is evaluated under a design and off-design operating condition. The performance verification experiments are carried out in the wind tunnel with a specially designed setup. A comparison of the measured and computed performance shows good agreement.