[{"data":1,"prerenderedAt":329},["ShallowReactive",2],{"blog:\u002Fen\u002Fblog\u002Fshallow-geothermal-heating-cooling-buildings":3},{"id":4,"title":5,"author":6,"body":7,"cardImage":300,"category":301,"date":302,"description":13,"draft":303,"excerpt":300,"extension":304,"footerCta":305,"hero":310,"locale":319,"meta":320,"navigation":321,"path":322,"seo":323,"slug":326,"stem":327,"__hash__":328},"blog\u002Fen\u002Fblog\u002Fshallow-geothermal-heating-cooling-buildings.md","Shallow Geothermal Heating Cooling Buildings","Planeto Team",{"type":8,"value":9,"toc":281},"minimark",[10,14,22,25,30,33,36,39,47,51,56,59,62,73,76,79,82,88,92,95,98,105,127,130,133,137,140,143,146,149,152,156,159,162,166,172,178,184,190,196,202,206,209,213,216,220,223,227,236,242,246,254,257,265,271,276],[11,12,13],"p",{},"Two things are happening to European buildings at once. Heating has to be\ndecarbonised, which means fossil boilers are being legislated out on a timetable\nthat is now visible in most countries. And summers have become hot enough that\ncooling is no longer a luxury question; it is a habitability question,\nespecially in the top-floor flats of well-insulated new buildings.",[11,15,16,17,21],{},"Most technologies answer one of these problems and make the other worse.\n",[18,19,20],"strong",{},"Shallow geothermal"," is one of the few that answers both with the same pipes,\nand it does so in a way that quietly sidesteps a regulatory wall many owners hit\nwhen they go looking for air conditioning.",[11,23,24],{},"It is also expensive to get wrong, and a fair number of projects do get it\nwrong. So here is the honest version: what shallow geothermal genuinely delivers\nfor a house or a small apartment building, where it disappoints, and what\nseparates a project that performs for fifty years from one that limps.",[26,27,29],"h2",{"id":28},"what-shallow-geothermal-actually-means","What \"shallow geothermal\" actually means",[11,31,32],{},"Shallow geothermal uses the ground in the first few hundred metres below your\nbuilding as a heat source in winter and a heat sink in summer. Below roughly ten\nto fifteen metres, ground temperature stops following the seasons and settles at\nsomething close to the local annual average air temperature, typically 8 to\n14 °C across most of Europe, rising slowly with depth.",[11,34,35],{},"For a single house or a small apartment block, the usual configuration is one or\nseveral vertical boreholes, commonly somewhere between 50 and 300 metres deep,\neach containing a sealed loop of plastic pipe. A water-glycol mixture circulates\nthrough that loop, picks up heat from the surrounding rock, and delivers it to a\nheat pump that raises it to a useful temperature for underfloor heating or hot\nwater. Horizontal ground collectors and energy piles exist too, but boreholes\ndominate where land is scarce, as it is for most urban and suburban projects.",[11,37,38],{},"The scale is not marginal. In Switzerland alone, geothermal sources delivered\nabout 4.7 TWh of heat in 2024, roughly 5% of national heating demand, with\nborehole heat exchangers and ground registers accounting for around 82% of that.",[40,41],"article-image",{":height":42,":width":43,"alt":44,"caption":45,"src":46},"712","1191","Shallow geothermal borehole field sized in Planeto, with the annual supply curve and heating and cooling energy generation","A shallow borehole field and its annual supply curve: the heating and cooling energy it delivers across the year.","\u002Fimg\u002Fsolutions\u002Fthermal-energy-source-dimensioning\u002Fexcess-heatgeothermal-curves.jpg",[26,48,50],{"id":49},"why-owners-choose-it","Why owners choose it",[52,53,55],"h3",{"id":54},"_1-it-delivers-cooling-where-other-cooling-is-restricted","1. It delivers cooling where other cooling is restricted",[11,57,58],{},"This is the argument that converts people, and it is the least discussed.",[11,60,61],{},"Across much of Europe, building regulation treats active comfort cooling as\nsomething to be justified rather than assumed. The specific mechanism varies by\ncountry, region and sometimes municipality, but the pattern repeats: energy\ncodes that cap or scrutinise installed cooling capacity, requirements to\ndemonstrate that passive measures such as shading and night ventilation have\nbeen exhausted first, planning restrictions on visible outdoor units in dense or\nprotected streetscapes, noise limits at the neighbour's boundary, and the\nongoing F-gas phase-down tightening the refrigerant side. Owners who set out to\ninstall a conventional split system frequently discover that the answer is no,\nor yes-but-not-really.",[11,63,64,65,68,69,72],{},"Geothermal cooling behaves differently, because it is a fundamentally different\nmachine. In its passive form, variously called ",[18,66,67],{},"free cooling",", natural\ncooling or ",[18,70,71],{},"geocooling",", there is no compressor running at all. Warm water\nfrom the building's floor or ceiling circuits passes through a heat exchanger\nagainst the cold brine coming up from the boreholes, and the heat goes into the\nground. The only electricity consumed is a circulation pump. Depending on the\nsystem, delivering a unit of cooling this way typically costs somewhere between\na twentieth and a fortieth of the electricity a compressor chiller would use.",[11,74,75],{},"The regulatory consequence follows from the physics. There is no outdoor unit,\nso nothing to see from the street and nothing to hear from the neighbour's\nterrace. There is no additional refrigerant charge beyond what already sits\ninside the heat pump. Electricity consumption is small enough that it rarely\ntroubles an energy-performance calculation. In many jurisdictions this puts\ngeothermal cooling either outside the restrictions entirely or comfortably\ninside them, at a point where a conventional system would fail.",[11,77,78],{},"The comfort is also different in character. Cooling delivered through a floor\nslab or ceiling is radiant and even: no draught, no cold spot, no fan noise. It\ndoes not feel like air conditioning. It feels like the building is simply not\noverheating.",[11,80,81],{},"Two honest limits. Passive floor cooling delivers modest capacity, on the order\nof 15 to 25 W\u002Fm², which is enough to hold the summer peak down by several\ndegrees but not enough to behave like a split unit in a heatwave. And because\nthe surfaces are cold, dew point has to be controlled, which means proper\nflow-temperature control and, in humid climates, a separate provision for\ndehumidification.",[83,84,85],"blockquote",{},[11,86,87],{},"Rules differ substantially between countries and even between municipalities.\nTreat the above as the shape of the problem, not as legal advice for your\nsite.",[52,89,91],{"id":90},"_2-regeneration-cooling-makes-the-system-last-longer","2. Regeneration: cooling makes the system last longer",[11,93,94],{},"Here is the part that surprises people. Using the system for cooling does not\nwear it out. It does the opposite.",[11,96,97],{},"A borehole field used only for heating takes heat out of the ground every winter\nand gives nothing back except what nature slowly replenishes. Over decades, the\nrock around the boreholes cools. The drift is small year to year but cumulative,\nand over thirty to fifty years it can amount to several kelvin. Every degree the\nsource loses costs the heat pump efficiency, which means more electricity for\nthe same warmth. A field that was sized optimistically in year one can be\nvisibly underperforming by year twenty, and you cannot easily drill your way\nout of it afterwards.",[11,99,100,101,104],{},"Summer cooling reverses this. Every kilowatt-hour of heat you push into the\nground in July is a kilowatt-hour that does not have to be extracted from fresh\nrock in January. This is called ",[18,102,103],{},"regeneration",", and its effects compound:",[106,107,108,115,121],"ul",{},[109,110,111,114],"li",{},[18,112,113],{},"Long-term ground temperature stays stable"," instead of drifting down, so the\nseasonal efficiency you were promised in year one is roughly the efficiency\nyou still have in year forty.",[109,116,117,120],{},[18,118,119],{},"The field can often be smaller."," Because the ground recovers, it can be\ndesigned with fewer or shorter boreholes for the same heating output. Drilling\nis the single largest cost line in the project, so this goes directly to\ncapital cost.",[109,122,123,126],{},[18,124,125],{},"The same buried pipes do both jobs."," Cooling is not an add-on system; it is\na second use of an asset you already paid for.",[11,128,129],{},"It is genuinely rare for the comfort upgrade and the durability upgrade to be\nthe same investment. Here they are.",[11,131,132],{},"The caveat is that balance has to be designed rather than hoped for. A\ncooling-dominated building can push the ground the other way and drift warm,\nwhich degrades cooling performance over time. The point is not \"more\nregeneration is better\"; it is that the annual heat balance is a design\nvariable, and somebody has to calculate it.",[52,134,136],{"id":135},"_3-you-are-running-on-your-own-grid","3. You are running on your own grid",[11,138,139],{},"A borehole field is an energy source you own outright. The ground is not\nmetered, not traded, not subject to a carbon levy, and not exposed to anyone's\npipeline politics.",[11,141,142],{},"The only purchased input is the electricity the heat pump consumes, and that is\nthe smaller part of the equation. A well-designed ground-source system typically\nachieves a seasonal performance factor of roughly 4 to 5, against something\ncloser to 2.5 to 3.5 for air-source in the same building. At an SPF of 4, every\nunit of heat delivered to the building costs you a quarter of a unit of bought\nelectricity. The other three quarters come out of the ground for nothing,\nevery year, permanently.",[11,144,145],{},"The practical effect on your exposure is worth stating plainly. If electricity\nprices rise 50%, a direct-electric system's heating bill rises 50%. Yours rises\nby 50% of a quarter. There is no gas connection, no standing charge for one, no\nfuel delivery, no tank, no chimney, no boiler service, and no exposure to a fuel\nmarket at all.",[11,147,148],{},"The pairing with rooftop PV is unusually good, and not only for the obvious\nreason. Cooling demand peaks on bright hot afternoons, which is precisely when a\nPV array is producing most, so the cooling function tends to run on\nself-consumed electricity rather than imported. Winter heating is a poorer\nmatch, but the summer overlap is close to ideal.",[11,150,151],{},"At source, the heat is 100% renewable. The carbon footprint of the whole system\nis then set by where your electricity comes from, which is a variable you\ncontrol and which is decarbonising anyway.",[52,153,155],{"id":154},"_4-invisible-silent-and-long-lived","4. Invisible, silent, and long-lived",[11,157,158],{},"Boreholes are commonly credited with service lives of 50 to 100 years; the heat\npump itself is a 20 to 25 year component. Nothing is visible from the street,\nthere is no outdoor unit to age badly on a façade, and there is nothing for a\nneighbour to complain about at 6am. In conservation areas and dense streets,\nwhere an air-source outdoor unit is often the thing that gets refused, this\nmatters more than it sounds.",[11,160,161],{},"There is a resale argument too. A building with a permanent, low-carbon,\nnon-fossil heating and cooling system is not facing the replacement deadline\nthat a gas boiler is, and valuers have started to notice.",[26,163,165],{"id":164},"the-drawbacks-stated-fairly","The drawbacks, stated fairly",[11,167,168,171],{},[18,169,170],{},"The upfront cost is real."," Drilling dominates the budget and scales with\nmetres, geology and site access. A single-family installation is typically a\nfive-figure investment, materially more than an air-source heat pump and several\ntimes a gas boiler. Payback against air-source commonly lands somewhere in the 8\nto 15 year range and improves sharply in buildings with meaningful cooling\ndemand, because you are getting two systems for one. Against direct electric or\noil it is faster. Constrained urban sites, where a rig has to work in a small\ncourtyard, cost more.",[11,173,174,177],{},[18,175,176],{},"Not every site is permitted or suitable."," Drinking-water protection zones,\nkarst, artesian conditions, contaminated ground and certain swelling rock\nformations can make boreholes restricted or prohibited. Several European regions\npublish admissibility maps for precisely this reason, and the permitting process\ncan take months. Small plots may not offer enough separation between boreholes,\nwhich need meaningful spacing to avoid stealing heat from each other.",[11,179,180,183],{},[18,181,182],{},"It punishes bad design in a way a boiler does not."," An oversized boiler\nwastes money. An undersized borehole field is a performance problem you live\nwith for the life of the building, because adding boreholes afterwards means\nbringing a rig back to a finished site, if there is even space left. The hole in\nthe ground is the one decision you cannot iterate.",[11,185,186,189],{},[18,187,188],{},"It needs low-temperature emitters."," The efficiency case rests on delivering\nheat at 30 to 40 °C. Dropping a ground-source heat pump into an old radiator\ncircuit designed for 65 to 70 °C erodes the advantage badly. And passive cooling\nrequires cooled surfaces: floor, ceiling, or fan coils. Old radiators cannot\ncool.",[11,191,192,195],{},[18,193,194],{},"Construction is disruptive."," Drilling is days to weeks of rig, noise, water\nand spoil on site. Straightforward in new build; more intrusive in an occupied\nbuilding.",[11,197,198,201],{},[18,199,200],{},"Cooling capacity is finite."," Passive geocooling shaves the peak and holds the\nbuilding in a comfortable band. It will not hold 21 °C through a 38 °C week the\nway an oversized split system will, and it does not dehumidify on its own.",[26,203,205],{"id":204},"what-separates-a-good-geothermal-project-from-an-expensive-one","What separates a good geothermal project from an expensive one",[11,207,208],{},"Everything above is determined at design stage, before anyone drills. Three\nquestions decide the outcome.",[52,210,212],{"id":211},"how-much-heat-and-cold-does-this-building-actually-need-over-a-year-not-at-peak","How much heat and cold does this building actually need over a year, not at peak?",[11,214,215],{},"Rules of thumb in watts per square metre come from heating-dominated,\npoorly-insulated stock. Applied to a well-insulated modern building with real\nsummer cooling demand, they oversize the heating side and ignore the cooling\nside entirely. What matters for a borehole field is not the design-day peak but\nthe annual energy balance: how much you take out, how much you put back, and\nwhen.",[52,217,219],{"id":218},"how-much-ground-do-you-need-to-serve-that-for-fifty-years","How much ground do you need to serve that for fifty years?",[11,221,222],{},"The ground is a store with a memory, so the field has to be simulated over\ndecades with the real seasonal load profile, including the regeneration effect\nof summer cooling. A field sized on peak load alone will be either expensively\noversized or quietly undersized, and you will not find out which until year\nfifteen.",[52,224,226],{"id":225},"does-the-money-work-and-compared-to-what","Does the money work, and compared to what?",[11,228,229,230,235],{},"The options worth testing against each other are more numerous than most owners\nrealise: fewer deep boreholes versus more shallow ones, with and without PV,\nwith and without active regeneration, and (the one most often missed)\nindividual systems per building versus a small shared loop linking a handful of\nbuildings. ",[231,232,234],"a",{"href":233},"\u002Fsolutions\u002Flow-temperature-networks\u002F","Shared low-temperature loops","\nfrequently beat individual systems on both cost and performance, because loads\ndiversify, plant rooms consolidate, and a building that needs cooling can\nregenerate the ground for a neighbour that needs heat.",[40,237],{":height":42,":width":238,"alt":239,"caption":240,"src":241},"1190","A 5G low-temperature district heating and cooling network with shallow geothermal borehole fields, designed in Planeto","A shared low-temperature loop: several buildings, one set of borehole fields, and cooling loads that regenerate the ground for heating loads.","\u002Fimg\u002Fsolutions\u002Flow-temperature-networks\u002Flow-temperature-0.jpg",[26,243,245],{"id":244},"getting-the-answer-before-you-commit-capital","Getting the answer before you commit capital",[11,247,248,249,253],{},"This is the work Planeto exists to make faster and more reliable. Our platform,\n",[231,250,252],{"href":251},"\u002Fproduct\u002F","Tessa",", brings building demand, ground conditions, energy sources,\nnetwork layout and cost into a single model, so that these scenarios can be\nbuilt and compared in hours rather than weeks, and so that the answer you take\nto a drilling contractor is one you can defend.",[11,255,256],{},"For a single building or a small cluster, that means knowing whether the project\nworks, and at what size, before you commit capital. If it later grows into a\nshared loop across a neighbourhood, the same model carries through to detailed\ndesign.",[11,258,259,260,264],{},"And if you do not have a planning office already engaged, you do not need one to\nstart the conversation. Our energy engineers use Tessa on real projects every\nweek, and can\n",[231,261,263],{"href":262},"\u002Fservices\u002Ffeasibility-pre-feasibility-studies\u002F","run the feasibility work with you",",\nreview a design somebody has already proposed, or simply tell you whether your\nsite is worth pursuing at all.",[11,266,267],{},[231,268,270],{"href":269},"\u002Fproduct-demo\u002F?ref=blog-shallow-geothermal","Talk to our energy experts →",[272,273],"faq-section",{":items":274,"heading":275},"[{\"question\":\"Can a geothermal system really cool a building?\",\"answer\":\"Yes, and usually without a compressor. Cold brine from the boreholes is passed against the building's floor or ceiling circuits through a heat exchanger. Capacity is moderate and radiant rather than forced-air, so it holds the building in a comfortable band rather than delivering a cold blast.\"},{\"question\":\"Does using it for cooling shorten the system's life?\",\"answer\":\"The opposite. Summer heat injected into the ground regenerates it, counteracting the long-term temperature drift that heating-only fields suffer, and protecting efficiency over the decades.\"},{\"question\":\"How deep do the boreholes go?\",\"answer\":\"Commonly 50 to 300 metres for residential projects, with the total depth driven by heat demand and ground thermal conductivity rather than by a fixed rule.\"},{\"question\":\"Will I need a permit?\",\"answer\":\"Almost certainly. Most jurisdictions regulate drilling, many publish maps of where boreholes are restricted or prohibited, and lead times of several months are normal. Check this before anything else; it is the fastest way to find out whether a project is possible at all.\"},{\"question\":\"Does it work in an existing building?\",\"answer\":\"It can, but the emitters usually decide. Buildings with underfloor heating or generously sized radiators adapt well. Buildings running high-temperature radiators need that addressed first, or the efficiency case weakens considerably. They also cannot deliver cooling at all.\"}]","Frequently asked questions",[277,278],"cta-banner",{"heading":279,"secondary-label":280,"secondary-to":269},"Find out whether shallow geothermal works on your site","Talk to our energy experts",{"title":282,"searchDepth":283,"depth":283,"links":284},"",2,[285,286,293,294,299],{"id":28,"depth":283,"text":29},{"id":49,"depth":283,"text":50,"children":287},[288,290,291,292],{"id":54,"depth":289,"text":55},3,{"id":90,"depth":289,"text":91},{"id":135,"depth":289,"text":136},{"id":154,"depth":289,"text":155},{"id":164,"depth":283,"text":165},{"id":204,"depth":283,"text":205,"children":295},[296,297,298],{"id":211,"depth":289,"text":212},{"id":218,"depth":289,"text":219},{"id":225,"depth":289,"text":226},{"id":244,"depth":283,"text":245},null,"Geothermal Energy","2026-09-21",false,"md",{"heading":279,"primary":306,"secondary":309},{"label":307,"to":308},"Start for free","https:\u002F\u002Ftessa.planeto-energy.ch",{"label":280,"to":269},{"heading":311,"subhead":312,"image":313,"primary":317,"secondary":318},"Shallow Geothermal for Homes and Small Apartment Buildings: Heating, Cooling, and What Nobody Tells You","Heating has to be decarbonised and summers have become hot enough that cooling is a habitability question. Shallow geothermal answers both with the same pipes, but it is expensive to get wrong. Here is what it genuinely delivers, where it disappoints, and what decides the outcome before anyone drills.",{"src":314,"alt":315,"width":316,"height":316},"\u002Fimg\u002Fblog\u002Fshallow-geothermal-hero.png","Shallow geothermal boreholes under a building, paired with rooftop PV",1120,{"label":307,"to":308},{"label":280,"to":269},"en",{},true,"\u002Fen\u002Fblog\u002Fshallow-geothermal-heating-cooling-buildings",{"title":324,"description":325,"ogImage":314},"Shallow Geothermal: Heating and Cooling for Buildings | Planeto","How shallow geothermal heats and cools homes and small apartment buildings, why regeneration makes it last longer, and the drawbacks worth knowing first.","shallow-geothermal-heating-cooling-buildings","en\u002Fblog\u002Fshallow-geothermal-heating-cooling-buildings","lg0NTGlRJhNZzmiodhcU3IU_Azk0caZ1Py13RO_YN0A",1790169687561]