The Potential of Hydrogen Enriched Natural Gas deriving from Power-to-Gas option in Building Energy Retrofitting

doi:10.1016/j.enbuild.2017.05.049

Energy and Buildings

Volume 149, 15 August 2017, Pages 424-436

https://doi.org/10.1016/j.enbuild.2017.05.049 Get rights and content

Highlights

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Hybrid systems in energy retrofitting of existing buildings.
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Three energy system layouts are designed involving hydrogen enriched natural gas blends.
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Sensitivity analysis to evaluate the technical feasibility of the proposed plant lay-outs.
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Power-to-gas option by means of hydrogen shows high potential.
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The role of H2NG blends in existing buildings and the effects on conventional technologies for heating.

Abstract

This paper deals with the role of Hydrogen enriched Natural Gas (H2NG) in Hybrid Energy Systems for energy refurbishment purposes. In detail, three different plant layout options were investigated. A photovoltaics (PV) array and two-stage electric heat pump (EHP), a hybrid photovoltaic thermal solar collectors combined to gas heat pump (GHP) fuelled with H2NG, and a CHP fuelled with H2NG connected to a two-stage EHP were compared. The required receiving surfaces of PV array were estimated for three different direct normal irradiation (DNI) values in Italy in order to assess how the available roof surface affects the layout choice. A sensitivity analysis was carried out with varying the building power to heat ratio (PTHR) and the hydrogen volumetric fraction in the H2NG mixtures to assess the primary energy consumption (PEC) and renewable energy fraction. When feasible, the PV + EHP shows the best performance in terms of PEC with a solar energy share equal to 65%. In other cases, the PV/T + GHP fuelled with H2NG @30%vol. can be suitable for PTHR higher than 0.2 approximately. Furthermore, the third layout CHP + EHP is not competitive with the other solutions but, it is the best option where no roof surfaces are available for PV or PV/T installation.

Introduction

Rational energy utilization is still the aim of most policy interventions in the building sector along with the technical ones to reduce the energy demand towards the nZEB [1]. Renewable energy deployment is becoming an energy efficiency tool for building stock [2] accounting for landscaping impacts [3], connections with territorial well-established economics and effective use of available resources [4]. In recent years, research technological solutions for sustainable energy purposes, such as combined heat and power (CHP) system, electric heat pump (EHP) and photovoltaics (PV) have been widely investigated [5], [6], [7]. Yet, existing buildings greening is the main environmental and economic challenge due to their amount and their relative constraints as well as the required inter-disciplinarity approach [8]. Indeed, promising solutions such as PV + EHP are immediately feasible in new low energy buildings while, they are not suitable to be installed in the current built environment. So, alternative solutions related to the energy production should be taken into account to overcome such limits [9]. Hydrogen application at building scale received strong attention for dwellings located in Mediterranean and Northern Europe climate [10], [11]. But, it is remarkable that those pioneer projects are related only to new buildings. To manage the transition for the existing ones, the eco-fuels use appears as foreseeable in order to reduce carbon dioxide emissions, directly [12], [13]. In this framework, the hydrogen enriched natural gas blends are a viable option to feed current energy production devices and to mitigate the renewables capacity firming issues of the power grid [14], [15]. Indeed, the so-called power-to-gas is able to convert the RES electricity excess into renewable hydrogen to be injected into the natural gas pipelines [16], [17]. This power shifting way could be used to enhance the supply renewability in existing building stock. Indeed, this latter is composed by dwellings built after the Second World War to be renovated and cultural heritage or listed historic buildings to be preserved and make comfortable for modern use. The key driver of this study is to introduce renewable energy supply by means of Hybrid Systems as well as local production from solar energy. Where PV or PV/T cannot be installed on roof surface due to architectural and technical constraints, the power-to-gas scenario consisting of renewable hydrogen injected to NG pipelines is considered. The suitability of those blends with well-proven technologies is already demonstrated [18], [19].

This paper focuses on the role of hydrogen enriched natural gas (H2NG) in hybrid energy systems for energy refurbishment purposes, considering merchandised technologies such as photovoltaics (traditional and hybrid), combined heat and power plant (CHP) and heat pump (electric and gas driven). Moreover, a comparison between those systems was discussed in terms of primary energy saving and renewable energy fraction. To do so, the first step is to identify the viable hybrid systems solution and to evaluate their compatibility with hydrogen application.

Section snippets

Methodology

As reported in Fig. 1, the traditional separated generation layout was compared to three different plant layout options: the first one is composed of a PV array and a two-stage electric heat pump (EHP); the second one is composed of photovoltaic thermal hybrid solar collector and a adsorption gas heat pump fuelled with H2NG blends; in the end, the third one consists of a CHP fuelled with H2NG blends and a two-stage EHP. The systems energy balance was calculated over one year period implementing

Materials

In order to perform the simulations of all base scenarios, technical assumptions on devices efficiency, RES share and hydrogen energy share were made. Then, data from TABULA project [21] was selected to understand the common thermal and electric energy needs of real buildings and their different typologies. Moreover, renewable energy capability deriving from solar conversion was estimated by the use of the peak sun hour method. The advantage of peak sun hours is that they can be multiplied

Results and discussion

Since the aim of this study is to explore the opportunity to increase the renewables share in existing buildings, the authors found that the best solution, i.e. the solar heat pump (PV + HP + GRID), is not easily suitable for built-up areas due to several constraints. Therefore, strengths and weaknesses of hybrid systems involving solar energy were discussed once those solutions substitute the best one because not feasible. To account for the mentioned limitations, the foreseeable alternative was

Conclusions

The study explored the performance of three energy systems in building energy refurbishment involving the Hydrogen use. Furthermore, a sensitivity analysis, based on building energy characteristics, machines efficiency and geographical areas variations was performed to assess strengths and weaknesses of current technologies able to burn hydrogen blended to natural gas. The main findings can be outlined as follows:

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Solar heat pump represents the best energy solution for heating plant and it has

References (28)

E. Rodriguez-Ubinas et al.
Energy efficiency evaluation of zero energy houses
Energy Build.
(2014)
M.S. Todorovic et al.
In search for sustainable globally cost-effective energy efficient building solar system – heat recovery assisted building integrated PV powered heat pump for air-conditioning, water heating and water saving
Energy Build.
(2014)
L. de Santoli et al.
Single cylinder internal combustion engine fuelled with H2NG operating as micro-CHP for residential use: preliminary experimental analysis on energy performances and numerical simulations for LCOE assessment
Energy Proc.
(2015)
M.S. Todorovic et al.
Buildings energy sustainability and health research via interdisciplinarity and harmony
Energy Build.
(2012)
S. Barbarelli et al.
Transients analysis of a tidal currents self-balancing kinetic turbine with floating stabilizer
Appl. Energy
(2015)
G. Vialetto et al.
Innovative household systems based on solid oxide fuel cells for the Mediterranean climate
Int. J. Hydrogen Energy
(2015)
G. Vialetto et al.
Innovative household systems based on solid oxide fuel cells for a northern European climate
Renew. Energy
(2015)
F. Amrouche et al.
Toward hydrogen enriched natural gas “HCNG” fuel on the Algerian road
Int. J. Hydrogen Energy
(2011)
B. Nastasi
Renewable hydrogen potential for low-carbon retrofit of the building stocks
Energy Proc.
(2015)
S. Bennoua et al.
Role of hydrogen in resolving electricity grid issues
Int. J. Hydrogen Energy
(2015)

B. Nastasi et al.

RES (renewable energy sources) availability assessments for eco-fuels production at local scale: carbon avoidance costs associated to a hybrid biomass/H2NG-based energy scenario

Energy Proc.

(2015)

M.S. Todorović et al.

Historic building's holistic and sustainable deep energy refurbishment via BPS, energy efficiency and renewable energy – a case study

Energy Build.

(2015)

G. Lo Basso et al.

How to handle the Hydrogen enriched Natural Gas blends in combustion efficiency measurement procedure of conventional and condensing boilers

Energy

(2017)

F. Tabkhi et al.

A mathematical framework for modelling and evaluating natural gas pipeline networks under hydrogen injection

Int. J. Hydrogen Energy

(2008)

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The Potential of Hydrogen Enriched Natural Gas deriving from Power-to-Gas option in Building Energy Retrofitting

Highlights

Abstract

Introduction

Section snippets

Methodology

Materials

Results and discussion

Conclusions

Energy Build.

Energy Build.

Energy Proc.

Energy Build.

Appl. Energy

Int. J. Hydrogen Energy

Renew. Energy

Int. J. Hydrogen Energy

Energy Proc.

Int. J. Hydrogen Energy

Energy Proc.

Energy Build.

Energy

Int. J. Hydrogen Energy