Energy and climate change最新文献

The residential sector is targeted for emission reduction in the climate action plans of many countries. These plans typically focus on reducing the operational energy of the residential sector only, with little focus on the embodied emissions of its construction. To fully decabonise the residential sector both operational and embodied carbon emissions would need to be eliminated.

This paper presents whole life carbon quantification of the Irish residential sector, which aggregates the carbon emitted in operating the national housing stock, as well as the carbon emitted year on year in building and maintaining it. A detailed methodology is presented for both baselining, and forecasting, the emissions due to the residential sector. Operational emissions from space heating, hot water provision and electricity usage in the home are amalgamated. Embodied emissions, which are distributed across almost all categories of the national carbon inventory, are also estimated. The whole life carbon emissions of the residential sector account for approximately 25% of the total GHG emissions reported in the national carbon inventories.

Modelled forecasts to 2030 are presented for national plans that aim to reduce emissions through retrofit and electricity decarbonisation, but will result in increased embodied emissions through planned housing development. The current Climate Action Plan for reduction of residential sector operational carbon fall short of achieving sectoral target reductions. Additional measures will be required if the sector is to meet its proportional share and sectoral emission ceiling. Even if these are achieved, gains that might accrue from home retrofit and electricity decarbonisation will be negated by the growth in embodied emissions deriving from housing development outlined in government plans, when the sector is considered from a whole life carbon perspective.

Forecasts for operational emissions including business as usual and national sectoral targeted reduction scenarios of 40% are outlined. A range of scenarios are then presented to achieve emission reduction across the whole of the residential sector in line with the national 51% reduction targets. These will require; strategic targeting of the worst performing homes for retrofit first, complete decarbonisation of electricity, reduction in the size of future homes, as well as a major reduction in the embodied carbon of building materials used for residential construction. Activation, and renovation, of existing and vacant properties could accelerate the number of homes available while offsetting the need for extensive new construction.

State-level electricity standards are proliferating and becoming more ambitious, with numerous US states adopting a Renewable Portfolio Standard (RPS) and a small but increasing number of states participating in carbon pricing programs. The State of Hawai‘i has an ambitious RPS that requires 100% electricity generation through renewable sources by 2045. This study uses a general equilibrium model to compare a range of state-level carbon reduction strategies that achieve the same level of GHG emissions reductions in Hawai‘i as the RPS. We find that the RPS has regressive welfare outcomes. In contrast, an electric-sector-only carbon tax can be progressive if revenues are returned to households in equal-share dividends. Without dividends, there is little difference in welfare impacts between the RPS and electric-sector-only carbon tax. An economywide carbon tax has the lowest marginal cost of GHG abatement and highest level of electric vehicle adoption. When revenues are returned to households, the economywide carbon tax also has the most progressive welfare outcomes. Without revenue recycling to households, however, the economywide carbon tax yields the worst welfare impacts.

Global energy sector decarbonization efforts are contingent on technology choices for energy production and end-use in emerging markets such as India, where air conditioning (AC) is expected to be a major driver for electricity demand growth. Here, we assess the impact of demand and supply side-drivers on the long-term evolution of the electricity sector in India under various technology and policy scenarios. Our analysis is based on developing: (a) multiple demand scenarios produced from a bottom-up forecasting model with high temporal resolution that capture structural changes in electricity consumption resulting from (AC) and electric vehicle (EV) adoption, and (b) a multi-period power system capacity expansion model with high temporal resolution of grid operations to model supply-side evolution in response to changes in demand and technology and policy factors. Such a framework allows us to, for example, quantify the impacts of improving appliance efficiency standards for AC systems or shifts in EV charging patterns on power system decarbonization prospects. Under projected renewables and Li-ion storage cost declines, our modeling points to solar and wind generation contributing substantially (46–67%) to meet annual electricity demand in India by 2030. However, without appropriate policy measures to phase out existing coal generation, even such rapid adoption of variable renewable energy coupled with one or more technological levers such as low-cost energy storage and demand-side measures such as setting aggressive AC efficiency standards and deploying distribution level storage, are insufficient to reduce annual CO₂ emissions in 2050 vs. 2020 because of the relatively higher growth rate of projected electricity demand over this period. This suggests that deep decarbonization of India's power sector will require policy measures beyond efforts related to accelerating renewables deployment.

Policies for transitions to decarbonised energy and transport systems have implications for social welfare. Here we firstly investigate, via focus groups, public support for policies that have implications for energy and transport poverty in a country with a sizeable incidence of both, the United Kingdom (UK). We then examine which of the publics’ policy preferences concur with those of a wider group of expert stakeholders (n = 47), observing concurrence in the top choices of both for: (i) better public transport; mandating improved energy efficiency in (ii) rental housing and (iii) new homes; and (iv) expanding an income supplement scheme (such as the Warm Home Discount). While the public are relatively supportive of policy for electric vehicles, expert stakeholders see the shift to convergent electrification and digitalisation in domestic contexts as carrying risks for lower income households and those less digitally literate. We highlight that many of the public questioned view themselves as likely to be worthy of assistance, given the level of price inflation in the UK. We conclude that decarbonisation policies require careful attention not only to infrastructure, but to social welfare policy if they are to carry public support.

Imminent climate change impacts call for stronger energy system modeling approaches in order to design resilient communities. This study presents a flexible framework to integrate resilience analysis within the scope of long-term energy system optimization models (ESOMs). It employs a multi-objective resilience metric approach for energy system design, which allows for the independent representation and treatment of resilience and sustainability metrics. Several energy system-characterizing resilience and sustainability metrics are identified and integrated into a composite resilience metric, which is maximized as the objective function in an open-source ESOM. The cost performance of the resulting energy system design is tested across a range of short-term resilience scenarios, capturing different shocks. The method is demonstrated on two municipal case studies (located in China and Ghana). Three energy systems are designed and compared based on cost, emission, and resilience optimization objectives. Results illustrate a wide range of cost impacts depending on the system and resilience scenario. Systems designed based on a resilience objective offer more flexibility to adapt to and absorb shocks, thus reducing damage costs. Case study findings illustrate the value of incorporating resilience analysis into conventional ESOM and energy planning approaches in order to build more resilient communities.

Successful net zero governance calls for the fundamental reshaping of energy law, but it is not always receptive to changes required by decarbonization. If energy law's restrictive effects emerging from the field's legal traditions are not properly acknowledged and addressed, they may hamper the achievement of net zero carbon emissions by 2050 in the energy sector.

This paper presents, a unique topology for multilevel inverter based totally on cascaded connection of fundamental modules. The proposed circuit is able to operate for both symmetrical and asymmetric inverter, which can be used for fuel cell and photovoltaic systems. The magnitude of two dc sources in basic module can be adopted for symmetrical and asymmetrical structure. In the symmetrical multilevel inverter, the magnitude of dc source is identical for each module. However, the magnitude of dc source for basic modules is unequal in asymmetrical configuration and their magnitudes are achieved from binary and trinary progression. Comparison results prove that the proposed circuit requires a fewer number of components, reduced power loss and improve the efficiency of the inverter. Moreover, the total standing voltage on switches is acceptable compare to contemporary topologies. The proposed inverter can be implemented to low-medium power renewable energy systems. Simulation and experimental results for 11, 15 and 19-level inverters are analysed to validate the operation and performance of proposed topology.

Electric vehicles are supposed to play a leading role in the transition towards a low carbon society since they allow to substitute oil products with electricity as the main energy source for transportation. On the other hand, the diffusion of electric vehicles determines an increase in power demand with a consequent variation in the power supply mix. In accordance with this, it is mandatory to analyse how the supply mix changes, since the introduction of electric vehicles is significant from the sustainability point of view only if there is a reduction in emissions. To assess this condition for the Italian energy system, the present paper proposes a model developed in EnergyPLAN. Three different scenarios are tested in terms of the penetration of electric vehicles to understand which is the optimal trajectory for their diffusion. The analysis demonstrates that the Italian energy system can accommodate 7 million electric cars, namely about 25% of the total in 2040. A higher amount would determine an increase in carbon emissions.