In the arduous path towards sustainable development, research to obtain alternative fuels to fossils is presented as a key point. In this framework, two interesting actors have emerged to stay: biogas and biomethane.
Before going into the subject, let’s dig a bit into the current national gas system. Natural gas is one of the fuels most used by society, both in industry and in homes. Chemically, it is a gas composed mainly of methane 95-99% (CH4) and small proportions of other compounds. From its treatment, management and consumption in Spain, we must know two important aspects:
Almost all the natural gas we consume in Spain comesfrom non-renewable sources.
All this gas is mainly imported from countries such as Algeria, Norway, Nigeria or Qatar, either through the network of gas pipelines or through the transport of liquefied natural gas in large gas tankers.
While it is true that in comparison with other fuels the use of natural gas is better seen as it reduces emissions of CO2, particles and NOx, it isstill a fossil fuel. World natural gas reserves are estimated on 193 trillion m3, enough to cover demand for 52 years.
Biogas and biomethane are considered an interesting sustainable alternative in the fuel supply chain. Biogas is the fuel gas resulting from the degradation of organic compounds through a biological process. Depending on the precursors used, the volume composition of biogas ranges between 50% and 70% methane and 50% and 30% CO2. Biogas is an ideal fuel to generate heat or electricity, but, due to its low concentration of methane, it can not be used in its original form as a fuel for transportation nor can it be injected into the natural gas network. However, it can be ‘upgraded’ to be suitable for these last two applications. This improved biogas is known as biomethane. The CH4 / CO2 ratio of biomethane ranges between 95/5 and 99/1, a composition very similar to natural gas.
The key to make biogas and biomethane sustainable gases is to use as waste raw material that can not be reused or recycled. Not only do we talk about the typical urban waste that goes to the landfill, but also agricultural, livestock or wastewater are of high interest. These residues, when degraded, spontaneously emit methane into the atmosphere, whose impact on greenhouse emissions (GHG) is 21 times higher than CO2. In this way, this methane is generated in a controlled manner and after combustion is transformed into CO2, thus reducing the impact of GHG emissions.
The potential that Spain has to develop biomethane is very wide. Agriculture and livestock, one of the main engines of the national economy, generate an extensive amount of waste that contains very good “methanisable” characteristics. Likewise, every year each Spaniard generates half a tonne of direct waste, which is around 22,000 tonnes/year. The fact of being able to convert this waste into a fuel makes it possible to reduce greenhouse effect emissions at the same time as covering part of the imported natural gas consumption. The advantages are not only environmental; this new model allows the creation of new green jobs.
For the generation of biomethane there are multiple technologies, the anaerobic digestion followed by an upgrading is one of the best known and exploited. Anaerobic digestion consists on introducing a residue in a digester in absence of oxygen. In this digester the waste comes into contact with a biological culture (yes, bacteria) that are responsible for breaking down (hydrolysis) the long carbon chains, typical of organic matter, into smaller chains. After a few days, these bacteria continue to degrade the most simple carbon chains into methane. The product of this process is a mixture of gases, known as biogas, mainly composed of 60% methane, 40% CO2 and a minimum concentration of impurities such as hydrogen sulphide. In the process is generated a liquid waste called digestate that can be reused as a fertilizer because it is rich in nitrogen and phosphorus.
Once the anaerobic digestion is finished it is necessary to improve the quality of the biogas so that it can be used as fuel for vehicles or injected into the natural gas grid, this process is known as upgrading. After upgrading, the biomethane has a concentration close to 99%. There are different technologies that allow this process to be carried out:
Amine Absorption: Amines have high selectivity to attract CO2. The process is about “showering” the biogas with a dissolution of amines, which will sweep away the CO2, leaving the methane almost pure. The major disadvantage of this process is that the amines are not environmentally favourable.
Pressure swing adsorption (PSA): At high pressures, gases tend to be attracted to solid surfaces, or “adsorbed”. The higher the pressure, the more gas is adsorbed. Once the pressure is reduced the gas is released or un-adsorbed. This process requires a very high initial investment.
Membranes: This is a physical separation, as the biogas stream is passed through a porous membrane. The CO2 passes through the pores, while the methane remains. In order to obtain good separation yields, it is necessary to apply high pressures, making the process more expensive. In addition, methane slip is usually around 20% through the membrane pores, especially as they deteriorate.
Membrane contactor: These are the newest of those exposed. This technology agglutinates numerous membranes in the same shell, allowing the gas to pass through the inside of the membranes and a liquid flow through the casing. This combines physical and chemical separation. In this way, it is possible to work at lower pressures than in traditional membranes, as the water is able to dissolve part of the CO2, as well as reducing methane slip.
Once purified the biomethane would be almost ready for final use, or injection into the network. The last necessary process would be to compress it until the normal working pressure, for example, the natural gas grid is at a pressure of between 16-60 bars, or if it is desired to use as fuel a pressure of approximately 200 bars is required.
In some European countries such as Germany or Italy there are already industrial facilities that allow the production of biomethane, however, in Spain the biomethane market is still to be exploited. Aware of the potential that we have to develop the technology, policies are needed to make this market open gradually and be able to produce our own biomethane. This would reduce gas imports, the amount of waste produced and greenhouse gas emissions (and their corresponding EU fines) at the same time as creating jobs.
Undoubtedly, the electric sector in Spain has evolved during the past years, especially with regard to self-supply aspects. Time has elapsed since 2004, when the premium regime for the renewable energies was established. Gone are the first regulations about self-supply (RD 1699/2011) which for the first time considered the existence of individual facilities within the houses and set out the procedure and administrative conditions that they must fulfil, at the expense of a new Royal Decree that, due to policy issues, never was materialized.
Also far away is the regulation about the elimination of the bonus for sustainable energies, being the first blow suffered by this sector; what followed was not better. The subsequent law 24/2013 was branded as restrictive and discriminatory by the National Energy Commission (CNE), since not only was the self-supply not fostered among citizens, but also the register required complex administrative procedure and the document was not clear. Besides that, it referred to a potential economic tax on the self-consumed energy.
The following years were governed by some uncertainty, since the Royal Decree that should legally regulate all the proposed aspects was not published, thus, although the previous RD was still in force, it was feared that the new regulation was published at any moment. This caused a big paralysation of the electric and sustainable sector, which meant a fastdisappearance of companies and jobs.
Finally, the so-feared Royal Decree (RD 900/2015), better known as the “sun taxed RD”, saw the light. Its more controversial aspect was the establishment of a tax on the self-consumed energy, which raised up plenty of social and environmental organizations and official organisms against it. This legislation considered some transitory provisions exempting the small facilities of paying some taxes but, due to its temporary nature, citizens did not show interest on this kind of investments.
After some years of inactivity for this sector and by means of a government change, some months ago the Royal Decree – Law 15/2018 was released, opening the door for the active participation of the citizens in the electric market through the self-supply, in line with the current European energy policies. Recently, the Royal-Decree 244/2019 described and regulated the administrative, technical and economic conditions of the electric self-supply, including concepts such as the collective facilities or the net-billing, besides different modalities not considered up to date, which will facilitate the creation and incorporation of energy communities to the electric system.
This will enable a faster transition towards a more sustainable energy system thanks to the increase of the renewable energy generation rate. A fairer system, as the real needs of the consumers will be considered. A more autonomous market, since the dependency on external fossil fuels for power generation will be reduced.
R2CITIES, the Smart City project with which our city began the road towards efficiency and sustainability, has come to an end. Five years of project, and some more until it materialized, have been necessary to design, implement and evaluate the energy rehabilitation of three districts in cities as different socio-economically and urbanistically as Valladolid (in Spain), Genoa (in Italy) and Kartal (in Turkey). The project, funded by the European Commission under the FP7 program and coordinated by the CARTIF Technology Centre, has developed a methodology that guarantees success in its implementation for large-scale interventions in the energy rehabilitation of districts.
The main activities in Valladolid have been carried out in the neighborhood of Cuatro de Marzo. For a few months, the 13 residential buildings which have been rehabilitated energically are perfectly recognizable, although without losing the identity that marks the aesthetics of the neighborhood. Each of these properties has undergone a series of common modifications:
Installation of a thermal insulation in facade and roofs.
Replacing and bending windows.
Installation of solar panels to cover 60% of the demand for domestic hot water (DHW).
Renewal of boilers.
Installation of high efficiency luminaires in the common areas of buildings.
To complement the works and verify their effectiveness, the information on energy consumption and the comfort parameters of the interior of the dwellings (temperature, humidity and CO2 concentration) has been analyzed in order to evaluate the efficiency of the implemented solutions.
As I commented at the beginning of this text, R2CITIES was the first major city project that CARTIF proposed to the City Council and, therefore, to the city of Valladolid. In 2012, the concept of “Smart City” was still unknown to most citizens. In essence, what the EU tried to promote was the awareness of the consumers of resources, since our consumption was excessive and, what is worse, unsustainable. For this reason, these projects proposed solutions at the district (or neighborhood) scale to drastically improve the energy efficiency of those homes built decades ago, when the current environmental saving and sustainability standards were not determining factors for the construction sector.
Applying state-of-the-art technological solutions, these projects wanted to demonstrate, in a practical and measurable way, that the cost of electricity and gas could be reduced and, in addition, the comfort of the tenants of the dwellings could be considerably improved.
In the specific case of the Cuatro de Marzo, a residential neighborhood located in the center of Valladolid and whose homes were built in the 50s, numerous problems caused by moisture condensation in facades or in rooms that do not achieve rise of 17ºC with heating at full capacity have been solved. All this thanks to the isolation of the buildings. In addition to achieving significant savings in the heating bill, which is crucial in a region with a climate of extreme temperatures.
Additionally, and available to electric vehicle users throughout the city, it has been installed a recharging point powered by solar energy that captures a 3.7 kWpphotovoltaic marquee located inside the neighborhood.
Another feature common to smart city projects is that practical demonstrators are located in several cities. In the case of R2CITIES, the elected ones were the districts of Lavatrici, in Genoa, and Yakacik, in Kartal. In total, more than 49,500 m2 have been renovated in the three cities involved, achieving an overall reduction of 5,342,672 kWh / year in primary energy consumed (which represents an energy saving of 54%), while at the same time they stop emitting 2,393 t of CO2 per year.
Through the journey carried out in R2CITIES, we had the opportunity to expand our knowledge and experience in the energy renovation of urban residential spaces. With the future goal of having almost zero energy consumption cities, our project has implemented a set of technological solutions in the three demonstrators to reduce their energy demand and increase the use of renewable energy in them. This has allowed us to face both technical challenges and overcome numerous socio-economic barriers, allowing us to gain experience in large-scale district renewal strategies that we would like to share with all the professionals involved in the sector.
Both results obtained and experience gained, we share them with you through the material available on the website of our project, as well as we did in the conference By & For Citizens that was held in Valladolid on September 20 and 21. A conference where, in addition to R2CITIES ‘experience, the other city projects that we lead were presented: CITyFiED, REMOURBAN, mySMARTLife andUrbanGreenUp.
In a village of La Mancha, the name of which I have no desire to call to mind… an ingenious knight glimpses on the horizon old windmills. Believing that they were giants, he tries to defeat them with the help of his squire and the available weapons of the time. Do you recognise this scene? What if we frame it in the current era?
We are driving on the motorway and suddenly we glimpse on the horizon something that nowadays we do not consider giants: it is a wind farm composed of more than 20 wind turbines in charge of generating energy in a more sustainable way, but, once its function is fulfilled generate a large amount of waste that must be managed in an appropriate manner.
My question is, why do not we fight current problems with the resources of the moment: legislation, financing and research?
Allow me a brief description of the current situation. Since the second half of the eighteenth century, thanks to the industrial revolution, the ways of production and consumption changed radically, encouraging a rapid transformation of production systems to an unsustainable linear system due to the large amount of material and energy consumed, reinforced by the growth in consumption. Incompatible situation with a world of resources and capacity for adaptation limited to the growing impact generated by emissions of pollutants and the production of waste.
Therefore, with the aim of radically changing the current linear system of production and consumption, the European Commission, through the publication of a set of directives, has adopted an ambitious packageof new measures to assist in the transition of a Circular Economy (EC) that allows the use of resources in a more sustainable way. This fact will allow to close the life cycle of the products through greater recycling and reuse, that is, what is known as “cradle to the cradle”, bringing benefits both to the environment and to the economy.
From the conjunction of the above, together with the LIFE program and a consortium of companies of Castilla y León, including CARTIF, emerged LIFE REFIBRE, a demonstration project that aims to close the circle of a specific waste, the wind turbine blades.
The environmental problem generated by this type of waste is the result of two factors. On the one hand, the forecasts about the growing need to manage it, together with the inconvenience of its too large volume, give rise to problems in the land use of landfills where its final disposal is made. On the other, the management of this type of waste through other types of treatments, chemical or thermal, cause the emission of toxic substances into the atmosphere, as well as a greater energy consumption of these processes (Composites UK Lcd).
For all this, the actions that are being carried out within the LIFE REFIBRE project are aimed at reducing the waste of wind turbine blades sent to landfill through a mechanical recycling process, designed within the framework of the project, which will generate a new raw material, fiberglass. Once the fiberglass has been recovered and classified according to its size, it is introduced as a raw material in asphalt mixes. This process aims to achieve the improvement of the technical characteristics of this product, as well as a more sustainable management of wind turbine blades in disuse.
To conclude and as a farewell, I ask you a question: why do not we apply the concept of Circular Economy in our daily life? I can think of an example: reuse plastic bottles as pots.
It is weekend. Dinner with friends at home and the dishwasher is damaged. After washing the dishes by hand, I set out a question: ‘what do you value most when buying a dishwasher?
This is one of the situations where it is clear that the dishwasher exists because there is a service that generates its demand. If there were not dishes to be cleaned, there would hardly be an element dedicated to its cleaning, which has influence in ‘liberating our time’. So it must be designed specifically to satisfy with guarantees and quality the purpose for which it was designed.
Some people will tell us that, for the new purchase, we should value the price (an economic product can be tempting for our pocket); while others will advise us to evaluate the latest trends in this regard (a ‘designer’ dishwasher can incorporate the last cleaning technology). However, are these options the only ones to consider for the purchase? In addition, there could be people who advise you to seek the incorporation of eco-design criteria in order to our choice incorporates recycled materials, for example. So, what will be the most important criterion?
All the above options are attractive, of course, but I must admit that if I were at dinner, my advice would be towards buying the most efficient dishwasher. Why? Let’s see. I am going to convince you:
You are going to live for a long time with this electrical appliance, which consumes energy and water, so the fact that consumption would be as low as possible is important, affects our pocket.
Furthermore, do you believe that a surprisingly low price ensures not means a reduction in robustness? Perhaps, paying a little more you ensure a longer life of the appliance (and cleaner dishes).
According to dictionaries, the term ‘efficiency’ implies the ‘ability to have someone or something to achieve a certain effect’. This definition, which seems timeless and absolute, is really a term that must change and adapt to the particular context of each moment in history, and the current moment is not trivial. Efficiency implies that this ‘effect to achieve’ brings together all needs that the current context commits ourselves to satisfy.
A dishwasher must be able to clean the dishes correctly, with low electricity and water consumption (critical points in today’s society) and with a reasonable shelf life for the appliance, which will ensure that the consumption of resources is sustainable.
And, what if we associate this simile with roads?
The road exists to cover society’s need to transport goods and people from point A to point B. Everyone, like the dishwasher, should want an efficient road.
The road, as infrastructures, has its own environmental impact (associated with its ray materials, its manufacturing processes, etc), but it also has an influence on the impact associated with the consumption of the vehicles that pass through it, the accident rate, comfort, the state of the vehicles, the connectivity of different zones… Therefore, it should not matter to invest more resources and efforts at the beginning if later a return is obtained and the overall balance is positive (both from the environmental point of view as economic).
A road in good condition (efficient) can reduce the consumption of vehicles that travel up to 5% (EAPA). As an infrastructures, the construction and conservation of a road for 30 years represents less than 1% of the CO2 emissions of the vehicles that pass through it (EAPA).
So, why is not the concept of efficiency on the road as obvious as it is in a household appliance?
In the case of the dishwasher, the user chooses and funds it, pays for water, electricity, detergent, salt, dishes or repairs… according to his judgment. However, in the case of roads, the Administration, whit all the constraints, which manages and decides the actions on infrastructures. In addition, the saving obtained in the correct management of the infrastructures, are visible in the medium-long term and the fuel savings are diluted in many small saving for drivers, difficult to quantify. This may be the reason why Administration does not perceive an immediate real benefit, or perhaps it is not too attractive considering its electoral and budgetary pressure. The money also comes from the user’s pocket.
It is necessary to help administrations, from all the sectors involved in road transport, to understand that we are in a long distance race, to help internalize the concept of efficiency, and to evaluate the problems considering the global set of transport system as a whole, and not evaluate individually the multiple independent subsystems that compose it.
The environmental variable is improved thanks to a good conservation of the roads and the economic variable too, from a global point of view and including all the agents involved.
For some years, we have been listening to talking about smart cities, more sustainable environments… but, in some cases we do not know what kind of strategies could do our city to turn into one of them.
When we refer to Smart City, we talk about cities concerned with reducing energy consumption and emissions, cities that bring advances in information and communication technologies to their inhabitants and, ultimately, cities that seek improve the quality of life of its citizens taking advantage of many technological and non-technological solutions that are currently available in the market.
Although these solutions are available in the market, we have to wonder why these solutions are often not being applied. Sometimes, this is because of lack of funding; the least, of technical ignorance. But there is something in common when implementing this type of project; the difficulty of agreeing on all the agents involved in its execution. Citizens and experts, municipal agents and private companies, neighbourhood associations and users… all have to row in the same direction and work on the development of integral projects, instead of isolated solutions, in order to ensure cities of the future.
In CARTIF, we work to support European cities in this transition towards more intelligent and sustainable environments. Proof of this are the numerous projects that we are carrying out with this objective.
How can a city detect and analyse its needs and priorities? What technological solutions can be implemented to meet those needs? How a comprehensive project can be managed for the city? What business models or financial schemes can be applied? These are some of the issues which we address in this type of projects, and to answer them we work on methodologies that guide cities on the road towards their transformation into an Intelligent City.
One of the last lighthouse project in which CARTIF is working on is MAtchUP project (Maximizing the Upscaling and replication potential of high level urban transformation strategies), which has replicability as one of its main axes. When we look for solutions to satisfy the needs of our cities and their objectives, it is very important to have the experience of other European cities, where these solutions have already carried out. Knowing what has been the key to their success or how they have overcome certain barriers, is very useful information to achieve the replication of these solutions in other cities.
In MAtchUP, we not only work to ensure the success of the actions that are being carried out in its three demonstration cities: Valencia (Spain), Dresden (Germany) and Antalya (Turkey), but we work to ensure its future implementation in new scenarios: both within the same cities through the scaling of solutions in other areas of the city, and outside of them working on their replicability.
The actions can be framed in three fundamental pillars for urban regeneration: energy, mobility and information and communication technologies. These actions involve different agents, but above all, and fundamentally, involve citizens. They are the key factor of the new city model that promotes an integrating vision of all its agents. They create the city, live in it and enjoy it. And they are a primordial force that pushes the defined actions within the framework of the project.
MAtchUP continues the trajectory of demonstration projects at a city scale with which we have been working for years in CARTIF. But, unlike the previous ones, MAtchUP is not just a project for its lighthouse cities, but it delves much more into the work related to its follower cities; Herzliya (Israel), Ostend (Belgium), Skopje (Macedonia) and Kerava (Finland). In this way, the impact of the project will be much greater when working actively with seven cities, which will expand the useful and replicable results for all those cities that want to go further in their urban planning and in their transformation towards a more sustainable environment.
So, if we want to improve our cities, the best way is to take advantage of other experiences and replicating the successful solutions that have been carried out in other parts of the world. In CARTIF we want to collaborate with this dissemination of information and for this we have organized a conference in which smart cities will be the protagonists. BY & FOR CITIZENS will take place in Valladolid on September 20 and 21.
In this event, we will try to spread the experiences of a large panel of experts covering all aspects related to smart cities. We wait for you in Valladolid.
