scholarly journals Life Cycle Assessment of Irish District Heating Systems: A Comparison of Waste Heat Pump, Biomass-Based and Conventional Gas Boiler

2021 ◽  
Author(s):  
Conall Mahon ◽  
Maneesh Kumar Mediboyina ◽  
Donna Gartland ◽  
Fionnuala Murphy
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Natural Gas ◽  
Heat Pump ◽  
Waste Heat ◽  
Ghg Emissions ◽  
District Heating ◽  
Heating System ◽  
District Heating System ◽  
Ghg Reduction

Abstract This paper presents a life cycle assessment (LCA) of heat supply scenarios for the replacement of fossil-based energy systems through a case study focusing on an existing gas-fired boiler supplying heat for buildings located in Tallaght, Ireland. The three replacement systems considered are a waste heat fed heat pump district heating system (WHP-DH), a biomass CHP plant district heating system (BCHP-DH), and an individual gas boiler system (GB). The study found that both DH systems have lower environmental impact than the GB, with the BCHP-DH being superior to WHP-DH. However, using 2030 electricity data showed almost similar overall impacts for both the DH systems. Human toxicity potential (HTP) was highest among all impact categories studied and was due to the large additional infrastructure requirement for all three systems. Whereas the other impacts; Global warming (GWP), Fossil fuel depletion (FFD) and Eutrophication (EP), were due to involving usage of natural gas and electricity in use phase. The BCHP-DH showed reduced greenhouse gas (GHG) emissions by 45% and FFD by 73% compared to the GB system. Using 2030 electricity data, the WHP-DH decreased GHG emissions by 42% and FFD by 47%. Further, replacing biomethane with the natural gas in the DH systems decreased GWP by at least 11.4%. The present study concludes that the environmental benefit of a DH system is largely dependent on the carbon intensity of the electricity it uses, thus recommending the DH systems for large scale retrofitting schemes in Ireland to reach Europe’s 2030 GHG reduction targets.

scholarly journals Evaluating the Emissions of the Heat Supplied by District Heating Networks through A Life Cycle Perspective

2020 ◽  
Vol 2 (4) ◽  
pp. 392-405
Author(s):  
Francesco Neirotti ◽  
Michel Noussan ◽  
Marco Simonetti
Keyword(s):  
Life Cycle ◽  
Natural Gas ◽  
District Heating ◽  
Heating System ◽  
Plant Production ◽  
Life Cycle Assessment Methodology ◽  
District Heating System ◽  
Heating And Cooling ◽  
Life Cycle Perspective ◽  
Urban Contexts

The Life Cycle Assessment methodology has proven to be effective in evaluating the impacts of goods production throughout their life cycle. While many studies are available on specific products, in recent years a growing interest is related to the analysis of services, including energy supply for final customers. Different LCA evaluations are available for electricity, while the heating and cooling sector has not yet been properly investigated. The objective of this study is the analysis of the specific impacts of the heat supplied to the final users connected to a district heating system, in comparison with traditional individual natural gas boilers, which represent the baseline heating solution in several urban contexts in Europe. The results show that the comparison is heavily dependent on the allocation method used for combined heat and power plant production. District Heating impact on heat supplied to the users can vary from 0.10 to 0.47 kgCO2eq/kWh, while distributed natural gas boilers present an overall impact equal to 0.27 kgCO2eq/kWh.

Life cycle assessment of base–load heat sources for district heating system options

2011 ◽  
Vol 16 (3) ◽  
pp. 212-223 ◽  
Author(s):  
Saeed Ghafghazi ◽  
Taraneh Sowlati ◽  
Shahab Sokhansanj ◽  
Xiaotao Bi ◽  
Staffan Melin
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
District Heating ◽  
Heating System ◽  
Heat Sources ◽  
District Heating System ◽  
Base Load

scholarly journals Life Cycle Assessment of Low Temperature District Heating System in Gulbene Region

2020 ◽  
Vol 24 (2) ◽  
pp. 285-299
Author(s):  
Fabian Diaz ◽  
Ieva Pakere ◽  
Francesco Romagnoli
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Low Temperature ◽  
Environmental Impact ◽  
Renewable Energy Sources ◽  
District Heating ◽  
Heating System ◽  
Energy Sources ◽  
Hotspot Analysis ◽  
District Heating System

AbstractNew district heating system technologies have arisen in the last years to deliver economic and environmental benefits to residential and commercial buildings. The extensive ranges of equipment, energy sources, temperature profile configurations, size of the network, energy demand, and many other intrinsic variables, make it difficult to identify if a determined district heating option is potentially better than another in environmental terms. As for the economic evaluation, there are several tools decision-makers can rely on to assess environmental performance. The main challenge is to provide a holistic point of view for which lifespan and complexity of implementable, new technological systems can be an obstacle. For this reason, in this paper, a Life Cycle Assessment is performed upon a technical evaluation of several district heating configuration options for the Gulbene region in Latvia, where DH systems in most of the assessed parishes are already operating under medium temperature regimes, also known as third-generation district heating. The goal of the study is to understand the environmental impact of moving from the current DH system to a low temperature one. Results show a considerable environmental benefit if low-temperature profiles, combined with the use of renewable energy sources are adopted in the current DH systems. A hotspot analysis is also performed showing the use stage is the one carrying most of the burden across the project’s lifetime, followed by infrastructure construction; also showing that the refurbishment of buildings does not play a major role in the total environmental impact contribution.

Exergoeconomic Analysis of New High-Temperature District Heating System Based on Absorption Heat Pump Technology in Combined Heat and Power

2010 ◽  
Author(s):  
Fangtian Sun ◽  
Lin Fu ◽  
Shigang Zhang
Keyword(s):  
Heat Exchanger ◽  
Heat Pump ◽  
Waste Heat ◽  
District Heating ◽  
Heating System ◽  
Combined Heat And Power ◽  
Space Heating ◽  
Exergetic Efficiency ◽  
District Heating System ◽  
Absorption Heat Pump

Space heating area of district heating system of combined heat and power (CHP) accounts for approximately one third of total space heating area in Chinese northern cities. In the extraction condensing turbine combined heat and power system based on district heating network, there are a large number of low-grade waste heat in the condenser, and exergy loss in the steam-water heat exchanger and water-water heat exchanger. Based on absorption heat pump technology, a new high-temperature district heating technology (DHSAHP) was presented to improve the current district heating system of CHP. Absorption heat pumps are used to recycle low-temperature waste heat in condenser. Absorption heat pump type heat exchanger is used to reduce temperature of return water in primary heat network, and decrease irreversible loss. Where, DHSAHP was analyzed by thermodynamics and economics method, and evaluated by exergetic efficiency, exergetic output cost, exergetic cost difference and exergoeconomic factor. Compared with current district heating system of CHP, DHSAHP can decrease about 31.3% steam consumption, increase about 75% transmission and distribution capacity of the primary heating network. The evaluation results show that the exergetic efficiency of new district heating system of CHP based on the absorption cycle technology is higher 10.41% than that of current district heating system of CHP, whereas its exergetic cost is lower 36.6¥/GJ than that of the conventional district heating system. With the increase of annual heating time, economy efficiency of new district heating system of CHP becomes better. The DHSAHP has higher energy utilization efficiency and better economic benefits and provides a kind of better technological method to solve the main problems of cuurent district heating with CHP in China.

scholarly journals Thermal system-specific and net-zero carbon least-cost design of new houses in Canadian cold climates

2021 ◽  
Author(s):  
Brandon Wilbur
Keyword(s):  
Life Cycle ◽  
Heat Pump ◽  
Life Cycle Cost ◽  
Ghg Emissions ◽  
Building Design ◽  
Heating System ◽  
Carbon Intensity ◽  
Low Carbon ◽  
Net Zero ◽  
Zero Carbon

Whole-building model optimizations have been performed for a single-detached house in 5 locations with varying climates, electricity emissions factors, and energy costs. The multi-objective optimizations determine the life-cycle cost vs. operational greenhouse gas emissions Pareto front to discover the 30-year life-cycle least-cost building design heated 1) with natural gas, and 2) electrically using a) central air-source heat pump, b) ductless mini-split heat pump c)ground-source heat pump, and d) electric baseboard, accounting for both initial and operational energy-related costs. A net-zero carbon design with grid-tied photovoltaics is also optimized. Results indicate that heating system type influences the optimal enclosure design, and that neither building total energy use, nor space heating demand correspond to GHG emissions across heating system types. In each location, at least one type of all-electric design has a lower life-cycle cost than the optimized gas-heated model, and such designs can mitigate the majority of operational GHG emissions from new housing in locations with a low carbon intensity electricity supply.

Sign in / Sign up

Export Citation Format

Share Document