{"id":5546,"date":"2026-10-27T10:51:07","date_gmt":"2026-10-27T09:51:07","guid":{"rendered":"https:\/\/ghetool.eu\/?post_type=course&#038;p=5546"},"modified":"2026-10-27T10:51:08","modified_gmt":"2026-10-27T09:51:08","slug":"sistemas-hibridos-y-potencial-geotermico","status":"publish","type":"course","link":"https:\/\/ghetool.eu\/es_es\/course\/hybrid-systems-and-geothermal-potential\/","title":{"rendered":"Sistemas h\u00edbridos y potencial geot\u00e9rmico"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">In this part, everything will be about hybrid systems and, more specifically, hybrid geothermal systems. In this chapter, the concept of hybrid systems will be introduced, explaining the benefits and disadvantages. Next, the concept of geothermal potential will be shed light on, as well as the difference between system optimisation and system simulation.<\/p>\n\n\n\n\n\n\n\n<iframe title=\"Cap\u00edtulo 9.1: Sistemas h\u00edbridos y potencial geot\u00e9rmico\" width=\"800\" height=\"450\" src=\"https:\/\/www.youtube.com\/embed\/CwWW4dt-tZw?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe>\n\n\n\n\n\n\n\n\n\n\n\n<h2 class=\"wp-block-heading\">What are hybrid systems?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">For larger systems (think, for example, of a multi-utility building or 5th-generation district heating and cooling networks), the cumulative building demands are often very high, both in yearly demand and in resulting peak power. If 100% of this load should be delivered by only a single technology (in our case the borefield), that would probably require a lot of drilling. But perhaps there is not enough space to install the required borefield size, or there is not enough budget for this. Or, which is even more often the case, there is a more cost-effective alternative.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This is exactly where the concept of hybrid geothermal systems comes into view. A hybrid system, in GHEtool, is defined as <strong>a combination of multiple technologies that together provide the required building demand<\/strong>. For a hybrid geothermal system, as the name suggests, the geothermal technology plays a central role. Graphically, this is shown below.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><img fetchpriority=\"high\" decoding=\"async\" width=\"1024\" height=\"613\" src=\"https:\/\/ghetool.eu\/wp-content\/uploads\/2025\/01\/Hybrid-system-1024x613.png\" alt=\"Schematic representation of a hybrid system\" class=\"wp-image-3239\" srcset=\"https:\/\/ghetool.eu\/wp-content\/uploads\/2025\/01\/Hybrid-system-1024x613.png 1024w, https:\/\/ghetool.eu\/wp-content\/uploads\/2025\/01\/Hybrid-system-300x180.png 300w, https:\/\/ghetool.eu\/wp-content\/uploads\/2025\/01\/Hybrid-system-768x460.png 768w, https:\/\/ghetool.eu\/wp-content\/uploads\/2025\/01\/Hybrid-system-1536x919.png 1536w, https:\/\/ghetool.eu\/wp-content\/uploads\/2025\/01\/Hybrid-system-18x12.png 18w, https:\/\/ghetool.eu\/wp-content\/uploads\/2025\/01\/Hybrid-system.png 1838w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">Schematic representation of a hybrid system.<\/figcaption><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">The beauty of hybrid systems is that it does not matter which technologies are combined. Often, a borefield with a ground-source heat pump can be combined with an air-source heat pump to assist during the peak hours, or there is a district heating grid available to deliver the remaining part of the load. The ideal combination of technologies depends purely on your building demand (e.g. do we require a technology that can assist during high peak loads or just a technology that can run in baseload?), the required space (is there space to install an ASHP?) or existing systems (e.g. a gas boiler in renovation projects).<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Advantages of a hybrid system<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Hybrid geothermal systems are sometimes the only practical and feasible option for a project, for example when the available drilling area is limited. However, they also have other advantages:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Lower investment costs<\/strong>: Hybrid systems let you combine the strengths of different technologies to save money. Some technologies have lower upfront costs but higher operating costs, while borefields are often the most expensive part of the system from an investment perspective but offer excellent efficiency for the GSHP. For example, reducing the borefield size by 10% with a hybrid design can significantly lower capital expenses (CAPEX) and make the project more affordable.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Increased system reliability:<\/strong> By using multiple technologies, hybrid systems provide a natural backup. If one part fails, the other can still handle the building\u2019s needs.<\/p>\n\n\n\n<div class=\"note\">The design of backup systems is a separate design consideration. Typically, in the case of backup power, more than 100% of the actual required power to heat or cool your building is installed. This ensures that, if something goes wrong (or if heating and cooling needs have been underestimated), the system can still deliver the required load. <\/div>\n\n\n\n<h3 class=\"wp-block-heading\">Design challenges of a hybrid system<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Selecting the ideal combination of technologies is, of course, a first but rather straightforward design challenge, since this is often determined by the project boundaries (available roof top, noise restrictions, availability of district heating &#8230;). The major challenge is how to determine the required size of each technology so that in the end you have the best system. Since in this course everything is centred around the design of geothermal borefields, the central design question for any hybrid geothermal system is: \u201cWhat is the geothermal share we can get with a certain number of boreholes?\u201d<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This leads us straight to the concept of <strong>geothermal potential<\/strong>.<\/p>\n\n\n\n<div class=\"note\">In GHEtool Cloud, you actually do not need to care about what the hybrid technology is, since that in and of itself is of no importance for the geothermal simulation. In GHEtool, therefore, all hybrid systems are defined as &#8216;hybrid system for heating&#8217; or &#8216;hybrid system for cooling&#8217;, regardless of which technology (or technologies) is used for that. Using the results of the optimisation, the user can then see which hybrid technology can be useful for a particular project.<\/div>\n\n\n\n<h2 class=\"wp-block-heading\">What is geothermal potential?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">When it comes down to the geothermal potential of a borefield, there are three different options:<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Potential for power:<\/strong> the ability to provide more peak heating or cooling.<\/li>\n\n\n\n<li><strong>Potential for energy:<\/strong> the ability to exchange more energy with the ground over time, even if peak demands are already met.<\/li>\n\n\n\n<li><strong>No geothermal potential:<\/strong> when the borefield is already operating at its full capacity for both power and energy.<\/li>\n<\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">These three options are briefly explained below.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Geothermal potential for power<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Imagine a borefield with a temperature profile like the figure below. As is clear, the borefield reaches its limitations in the first year of operation with the maximum fluid temperature limit. It is not possible to increase the heat injection power, since that would exceed the temperature boundaries. Looking at the minimum fluid temperature, on the other hand, this does not come close to the minimum fluid temperature limit. This means we can extract more heat from the ground and provide our building with additional heating power. Therefore, we can conclude that this borefield has <strong>potential for power<\/strong>, in this case extraction power.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img decoding=\"async\" width=\"744\" height=\"400\" src=\"https:\/\/ghetool.eu\/wp-content\/uploads\/2026\/10\/Geothermal-potential-for-power.png\" alt=\"Hourly temperature profile of a building with potential for power.\" class=\"wp-image-5550\" srcset=\"https:\/\/ghetool.eu\/wp-content\/uploads\/2026\/10\/Geothermal-potential-for-power.png 744w, https:\/\/ghetool.eu\/wp-content\/uploads\/2026\/10\/Geothermal-potential-for-power-18x10.png 18w, https:\/\/ghetool.eu\/wp-content\/uploads\/2026\/10\/Geothermal-potential-for-power-300x161.png 300w\" sizes=\"(max-width: 744px) 100vw, 744px\" \/><figcaption class=\"wp-element-caption\">Hourly temperature profile of a building with potential for power.<\/figcaption><\/figure>\n<\/div>\n\n\n<h3 class=\"wp-block-heading\">Geothermal potential for energy<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">When the extraction load on the borefield above is increased, the temperature profile below is obtained. Now, the fluid temperature reaches the set limits in both the first and the last year of the simulation period, making it impossible to further increase the injection or extraction power, as the fluid limits would then be crossed again. However, this limitation only occurs in the first year for peak injection and in the last year for peak extraction. In the earlier years, there is still potential to extract more heat from the ground, while in the later years, there is potential to inject additional heat.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img decoding=\"async\" width=\"744\" height=\"400\" src=\"https:\/\/ghetool.eu\/wp-content\/uploads\/2026\/10\/Geothermal-potential-for-energy.png\" alt=\"Hourly temperature profile of a building with potential for energy.\" class=\"wp-image-5551\" srcset=\"https:\/\/ghetool.eu\/wp-content\/uploads\/2026\/10\/Geothermal-potential-for-energy.png 744w, https:\/\/ghetool.eu\/wp-content\/uploads\/2026\/10\/Geothermal-potential-for-energy-18x10.png 18w, https:\/\/ghetool.eu\/wp-content\/uploads\/2026\/10\/Geothermal-potential-for-energy-300x161.png 300w\" sizes=\"(max-width: 744px) 100vw, 744px\" \/><figcaption class=\"wp-element-caption\">Hourly temperature profile of a building with potential for energy.<\/figcaption><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">If we were to install additional geothermal power on this borefield, we could exchange more energy with the ground, but we would not be able to extract more power during peak periods. This is why we say that this borefield has <strong>potential for energy<\/strong> but not for power, as the peak power already reaches the temperature limitations.<\/p>\n\n\n\n<div class=\"advanced\"><p>In some cases, as shown above, installing additional cooling power to inject extra heat into the borefield during later years could also increase the geothermal heating power. By injecting more heat into the ground, we correct the imbalance in the ground, thereby creating additional potential for heating. In such a scenario, the borefield would revert to the previous category, regaining some potential for heating power.<\/p> <p>However, since this would be considered a &#8220;second-order&#8221; effect, it is typically neglected in the naming convention. As a result, we classify this borefield as having no potential for additional peak power but as having potential for extra energy exchange.<\/p><\/div>\n\n\n\n<h3 class=\"wp-block-heading\">No geothermal potential<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">In the temperature profile below, it is clear that there is <strong>no geothermal potential left<\/strong>, since the fluid temperatures reach both the maximum and minimum limits in every year of the simulation period.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"744\" height=\"400\" src=\"https:\/\/ghetool.eu\/wp-content\/uploads\/2026\/10\/No-geothermal-potential-1.png\" alt=\"\" class=\"wp-image-5548\" srcset=\"https:\/\/ghetool.eu\/wp-content\/uploads\/2026\/10\/No-geothermal-potential-1.png 744w, https:\/\/ghetool.eu\/wp-content\/uploads\/2026\/10\/No-geothermal-potential-1-300x161.png 300w, https:\/\/ghetool.eu\/wp-content\/uploads\/2026\/10\/No-geothermal-potential-1-18x10.png 18w\" sizes=\"(max-width: 744px) 100vw, 744px\" \/><figcaption class=\"wp-element-caption\">Hourly temperature profile of a building without any geothermal potential.<\/figcaption><\/figure>\n<\/div>\n\n\n<div class=\"note\">Strictly speaking, one could argue that there is still geothermal potential left, since in winter the maximum average fluid temperature is not met, and in summer the minimum one is not met either. There are, however, two important points to keep in mind: <ol><li>The concept of geothermal potential is always relative to the required building load. If the building has no cooling demand in winter, there is no potential for a higher injection load, since there is none.<\/li><li>It is, however, possible to think outside the box and to search for nearby buildings that could benefit from being connected to the same borefield. This is, for example, the case for buildings with opposite loads, like residential and office buildings or swimming pools and ice skating rinks.<\/li><\/ol><\/div>\n\n\n\n<div class=\"advanced\">With a time resolution of one hour, it is impossible to reach both the maximum and the minimum fluid temperature limits at the same time. This is where the definition of geothermal potential breaks down.<\/div>\n\n\n\n<h2 class=\"wp-block-heading\">The difference between optimising and simulating a hybrid system<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">In this part, two different approaches to designing hybrid systems will be discussed, namely the optimisation and the simulation of hybrid systems. Although both are complementary, it is important to understand their fundamental differences in order to know when to use which approach.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Optimising hybrid systems<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">When you are optimising a hybrid geothermal system, the central question is always: \u201cWhat can we do with a certain borefield size?\u201d, directly linking the design of the system with the concept of geothermal potential. In other words, it is a <strong>borefield-first methodology<\/strong> where the goal is to first get as much power (<a href=\"https:\/\/ghetool.eu\/course\/optimise-hybrid-system-for-maximum-power\">Part 9.2<\/a>) or energy (<a href=\"https:\/\/ghetool.eu\/course\/optimise-hybrid-system-for-maximum-energy\/\">Part 9.3<\/a>) out of the geothermal borefield, and what it cannot deliver should be delivered by something else. It wants to get the most out of your (probably) most expensive component.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Simulating hybrid systems<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">When you are simulating a hybrid geothermal system, the story is slightly different. Here, you select a priori the size of each hybrid technology and the temperature threshold above or below which the hybrid technology should be turned on. For example, when the outside air is above 12\u00b0C, it is probably more efficient to run an ASHP instead of a GSHP. In that case, you can simply say that x kW of ASHP turns on above 12\u00b0C. This approach can also be seen as <strong>hybrid-first<\/strong>, since, based on the set thresholds, it first takes part of the load away from the borefield, after which the borefield can simply be simulated as before.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This simulation approach is faster than the optimisation one, but it will not give you the same geothermal share, since it is not directly linked to the concept of geothermal potential. This will be discussed in <a href=\"https:\/\/ghetool.eu\/course\/simulate-hybrid-system\/\">Part 9.5<\/a>.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Conclusion<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">In this chapter, the concept of hybrid systems was introduced, explaining both the advantages and disadvantages, as well as the concept of geothermal potential. It was discussed that the design of these hybrid systems, especially the question of what the geothermal share was in a certain hybrid geothermal system, was far from trivial, and that there are different ways of looking at this problem, depending on whether you want to optimise the hybrid system or just simulate it.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In the chapters to come, different design methodologies for hybrid systems will be discussed, each with its own particular use case, advantages and disadvantages. Together, they will act like a toolbox from which the borefield designer can pick and combine whatever they need to make an informed decision on the final system.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">References<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Peere, W. (2025). Three ways to design a hybrid geothermal heating and cooling system for an office building. In <em>Proceedings of Geo-Rin Conference<\/em>. Benasque (Spain), 2-6 June 2025. [<a href=\"https:\/\/dialnet.unirioja.es\/servlet\/articulo?codigo=10467989\" target=\"_blank\" rel=\"noopener\">online<\/a>]<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Questions<\/h2>\n\n\n\n<div class=\"question\" data-chapter=\"1\">In the next part, the concept of regeneration will be introduced. Regeneration has the goal of reducing the geothermal imbalance by, for example, connecting solar thermal panels to the borefield in order to inject extra heat into it. Is regeneration also a hybrid system according to the definition used here?<\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>En este cap\u00edtulo se presentar\u00e1 el concepto de sistemas h\u00edbridos, junto con el de potencial geot\u00e9rmico.<\/p>","protected":false},"template":"","section":[120],"chapter":[150],"authors":[39],"class_list":["post-5546","course","type-course","status-publish","hentry","section-chapter-1","chapter-part-9","authors-wouter-peere"],"_links":{"self":[{"href":"https:\/\/ghetool.eu\/es_es\/wp-json\/wp\/v2\/course\/5546","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ghetool.eu\/es_es\/wp-json\/wp\/v2\/course"}],"about":[{"href":"https:\/\/ghetool.eu\/es_es\/wp-json\/wp\/v2\/types\/course"}],"wp:attachment":[{"href":"https:\/\/ghetool.eu\/es_es\/wp-json\/wp\/v2\/media?parent=5546"}],"wp:term":[{"taxonomy":"section","embeddable":true,"href":"https:\/\/ghetool.eu\/es_es\/wp-json\/wp\/v2\/section?post=5546"},{"taxonomy":"chapter","embeddable":true,"href":"https:\/\/ghetool.eu\/es_es\/wp-json\/wp\/v2\/chapter?post=5546"},{"taxonomy":"authors","embeddable":true,"href":"https:\/\/ghetool.eu\/es_es\/wp-json\/wp\/v2\/authors?post=5546"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}