All about Geothermal HVAC. The benefits outweigh the negatives.

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@tc9148 Ай бұрын

Agree 100%. We live in a large community that requires geothermal for all new homes built. It has been a big win for us for all the reasons you mentioned - no ugly outside compressors and electric costs much lower.

@BrentHull Ай бұрын

Great, thanks for the feedback.

@johnd.4385 Ай бұрын

Good video. I’m an engineer. I have geothermal in my house and in our office building. Here in coastal virginia it is easy to drill wells in the sandy soil, so the well costs are reasonable. A rule of thumb is one well per ton of A/C. Thanks for addressing this subject !

@BrentHull Ай бұрын

Thanks for sharing.

@bigdreamsonsmallacres 17 сағат бұрын

Any chance you do consulting on the side? I’m a DIY guy but want someone to check my efficiency and design plans. Located in VA

@johnd.4385 2 сағат бұрын

@@bigdreamsonsmallacres sure, I’d be glad to look over your plans and offer my thoughts (in an unofficial capacity of course) whats your email address?

@gregorynuttall Ай бұрын

I'm a huge fan of geothermal. Makes me wonder if we'll ever have a community scale geothermal heat pump wells like a public utility connected to the whole neighborhood.

@BrentHull Ай бұрын

Great question.

@pin65371 Ай бұрын

@@BrentHull there is one that was built in Alberta Canada. It seems like it worked alright but the idea was abandoned when the heat pumps reached end of life. The project is called Drakes Landing. There were a lot of mistakes made but it was also a first of its kind project. Also the fact that it worked well for so long with all the mistakes in an area where it reaches -40 during the winter shows it would be possible to make work in many areas.

@Real_Tim_S Ай бұрын

You mean "again?" We used to do district scale stuff before we started marketing all these electric gizmos... 100+ years ago. A lot of these "everything must go electric" mandates miss a huge opportunity to go back to higher efficiency district scale energy solutions - for example if you have an area with a lot of houses and businesses that need heat and electricity, you could take waste heat from the plant and send that out to the district for direct consumption - this is called combined heat and power (CHP, this one is not the law enforcement agency in California). For any combustion based generator, the conversion from heat+volume expansion is about 33-40%, that other 60-67% is just dumped into the atmosphere as waste heat (so called simple cycle plants - the biggest structure space claim at a nuclear power plant is the familiar cooling towers, just there to dump waste heat into the air), or in more efficient plants exhaust heat is recovered and turned into steam, which turns additional electrical generation, so that as much at 80-85% of the energy is recovered (these are called combined cycle plants). That heat could just as easily be put into a pipe and sent out to do heating work, instead of being converted to electricity and then back to heat, losing a bit of efficiency at each conversion step. There are similarly district cooling plants (still) in operation - all that extra generation capacity at night when the air is coolest is the most efficient time to reject stored heat (or in effect, to store cold). This extra generation can be used to make ice... you remember Ice Boxes? Before everyone had a personal refrigerator? Now we can create that ice in a warehouse-sized water tank at night maximizing the power plant's output and efficiency without a lot of load variation, and during the day that ice can absorb heat from the town/city with a larger water loop. It emulates the work of a ground loop, but on an industrial scale. None of this is new, and I'm glad that Brent is talking about this - I think some of the forgotten building science from back when engineers were steam powered and every bit of efficiency had to be squeezed out of every ounce of energy, is probably worth a come-back story of its own.

@Senthiuz Ай бұрын

In the UK, the Mines Authority is working on using shuttered coal mines as giant geothermal set ups to provide district heating.

@kennixox262 Ай бұрын

There area hand full of subdivisions in New England that have done just that. This is the exception rather than the rule however.

@OnkelPHMagee Ай бұрын

As someone outside the business, I really appreciate this kind of intro. to the topic.

@BrentHull Ай бұрын

Glad to hear it!

@lcarsng Ай бұрын

You have captured my imagination with traditional building techniques, proper moldings, wood paneling, shadow lines, classical greek/roman proportions, etc. Lately, I've been watching college lectures on these subjects and more. Though I'm just a non-rich homeowner and a layperson, I share your passion for building excellence and it's my dream to work with you one day.... even if it's to make a tiny shack with an old soul.

@BrentHull Ай бұрын

Nice. Thanks for sharing.

@JoshPiland Ай бұрын

Building Science Brent, nice! Designing with sense is beautiful.

@BrentHull Ай бұрын

Haha, thanks!

@chateaugrief Ай бұрын

Wanted to do geothermal on a newbuild but waiting for my state (California) to catch up with the times and not require prohibitive specialized engineer. More videos like these go a long way towards educating people about the existence and benefits of these systems.

@BrentHull Ай бұрын

Nice. THx.

@theodorepollock4019 Ай бұрын

Geothermal is great stuff, but there some issues in this video. 1) Freon is just a brand name for some old refrigerants that are no longer in use. 2) Using geothermal does not get rid of compressors. Some limited cooling applications (perhaps common in Texas, I don't know) can use the water directly from the geothermal loop. Most geothermal cooling systems use a compressor and reject heat to the geothermal loop. Any kind of geothermal heating uses a compressor to pull heat from the geothermal loop and reject the heat inside the home. The geothermal loop makes heat gathering and heat rejection more efficient - that's the reason to use geothermal over air source heat pumps.

@BrentHull Ай бұрын

Ok, Thanks.

@TofuInc Ай бұрын

Yeah, all the terms he was using and his descriptions were driving me crazy. You can tell there was little to no research that went into the video, just a guy rambling in front of a camera with a white board.

@everydazetuesday Ай бұрын

i often wonder if 4 to 6 houses on a city block could leverage the common yard space and make this system work cooperatively?

@jonathanboeckling8401 Ай бұрын

YES. Very easy and benefits increase on size.

@BrentHull Ай бұрын

Great question. I suspect so.

@Jared_Albert Ай бұрын

Thank you for tackling this

@BrentHull Ай бұрын

THanks for watching.

@oskoss92 Ай бұрын

Really excited to look more into this. Any recommendations on specific contracters to work with in texas?

@BrentHull Ай бұрын

Miller engineering is who we use. THx.

@kennixox262 Ай бұрын

Built my house in 2017, the area which I live makes it nearly impossible to get a permit for deep geo thermal heat pumps. Instead, we did a 5 zone ducted Mitsubishi heat pump. Large homes near me, 20,000 monster homes oddly have as you mentioned a multitude of standard compressors, 8 or more units on the roofs. You would think that homes in that price range would have a water chilled system.

@BrentHull Ай бұрын

Agreed. Thx.

@a97chrjo Ай бұрын

In Sweden, northern Europe, it's common for heating in houses from around 1500 square feet (150 square meters) and up. It has been common for the last 25-30 years. After about 20 years you have to change the indoor part of the system. Otherwise it's a problem free setup.

@BrentHull Ай бұрын

Thanks for the insight.

@DerekWoolverton Ай бұрын

I would love to see the cost come down even further on drilling and installation, it seems it is still a niche and therefor each job is custom. Probably still have refrigerant gasses somewhere in the system, just don't have to have anything outside. Our refrigerators and freezers have compressors for example. The high efficiency house competition in Washington DC has showcased A/C systems hooked to hot water for decades, but good luck finding an A/C manufacture who will let you take a tap off their unit to capture waste heat and still have a warrantee. So many technical possibility, but still so far away from the average homeowner.

@BrentHull Ай бұрын

OK. Thx.

@jamesg6071 Ай бұрын

Great idea for larger homes but I don’t see the capex coming down much cheaper. Drilling costs money.. I believe something like what gree and others are doing with vapor injection on heat pumps is going to be much more mainstream. VRF is much more cost effective for one large residence

@BrentHull Ай бұрын

Ok, thanks.

@morganoverstreet6824 Ай бұрын

Building a 5k SF home now. Geo ended up being less than 2 heat pumps after the tax credit

@BrentHull Ай бұрын

Nice, thanks for sharing.

@randomuser6789 Ай бұрын

Very interesting

@BrentHull Ай бұрын

Thanks!

@Real_Tim_S Ай бұрын

The older I get, the more I realize the older guys were right - "Silence is Golden™". I generally prefer a quiet well designed hydronic system to a force air system and something-to-air condensers outside the house pushing heat into the immediate area and adding to noise pollution. As long as your water table is high enough, a ground loop geothermal system is going to be ideal of most small to large properties. Water has a much higher thermal mass than air, so you need to move a lot less of it to transfer the same amount of BTUs/hr. That is the reason I prefer an HVAC&R design based on a "spine" hydronic loop - using smaller, higher efficiency, reversible heat+cool units to do the final push to what is needed in a local zone. The Mitsubishi CityMulti system is built like this, but rare in North America in smaller scale projects. Because the individual zones have their own unit and the hydronic spine passes all of the units (in larger buildings there may be an intermediate floor management unit), it allows pushing heat pulled from one zone into another - before having to reject it outside the building envelope. I've been begging companies like Mitsubishi and Carrier to integrate more and more thermal devices into their hydronic type platforms - think of having a refrigerator/freezer and a water-heater connected as loads to a hydronic system. You're already doing the same thing on a larger scale with your house and the outside environment. Extracting heat from one side of an insulated volume and rejecting that heat to the other side (heating versus cooling just changes the direction of the heat flow). Imagine how the total efficiency of a water heater would increase if it was sourcing heat from the room the water heater was in that escaped the insulation barrier and then pumped it back into the water heater - but that's only the second order efficiency improvement. Not being a load that has to be calculated for that room is the first order efficiency improvement! thinking the refrigerator or freezer example, a normal appliance must extract heat energy from the inside of the insulated box, and then reject that heat into the room via a coil that is either integral to the appliance (right inside its skin) or right up the back (getting covered in dust, because when is the last time you remember pulling out your fridge to clean the coils?). If that heat energy isn't getting pushed into your kitchen, then you don't have to remove it with an HVAC system - that's where integrating the R (refrigeration) into the overall Heating Ventilation Air Conditioning & Refrigeration (HVAC&R) pays off. Unfortunately, doing this with modern refrigerators and freezers pretty much requires the commercial sized ones that were designed to be serviced and have fairly common off-the-shelf parts like compressors that can be swapped with water-loop plated heat exchangers. Bigger houses only need apply for this modification right now.

@BrentHull Ай бұрын

Wow, thanks.

@scottgillespie6892 Ай бұрын

What about heat? How do I keep my house here in WI at 72 degrees in January?

@BrentHull Ай бұрын

IT works both ways. no problem.

@JustinPaone1 Ай бұрын

Not an engineer, but with clay soils (which Texas has a lot of) it makes sense to start the lines 5 feet below grade as clay soils tend to have less evaporation 5 ft down, which means less contraction of soils, which = more stability. If expansive soils can lift fountains. Causing damage to a water line is also possible. In fact, I've seen it happen. If the lines do need to be replaced/repaired, are they accessible, or does it require drilling a new well?

@BrentHull Ай бұрын

So far, that is not the weak point. Lines are replacable if they did fail.

@T_157-40 Ай бұрын

Agree

@BrentHull Ай бұрын

Thanks!

@cborecky Ай бұрын

For economic comparison, my solar panels and wiring cost $18k. They cover 60% of my entire home's electrical needs - so heating/cooling plus an appliance or two! So let's say $10k of my project's cost reduced my heating/cooling bill to zero for the next 25 years. Installing geothermal would have to be very, very cheap to compete with that. Even if it was only $10k it wouldn't make sense on my small house because it would still come with an electric bill.

@BrentHull Ай бұрын

ok, thanks.

@TofuInc Ай бұрын

4:37 Normal condensing temperature regardless of outdoor temperature is 100° so at 106° air temp with a modern system you're looking at a condensing temp of ~118°, you're still able to reject plenty of heat and keep that head pressure below 400psi. Sure there is some loss of efficiency but not near as much as you would think. Going from 95° to 105° on a 10 year old 14 SEER system you will only drop from 13 EER to a 11.8 EER, modern variable speed systems close that gap even further. Anyone choosing to design a system to cool a 15k sqft space with 10+ condensing units should be fired, that's not how its done. I would argue a single air source VRF system, designed properly could rival a geothermal system when considering life cycle cost. VRF systems are available up to 60+ tons (equal to 12 5 ton condensers). In a large space you also will have areas that need cooling while others need heating. VRF systems have heat recovery so they can basically shuffle the heat around the building, no need to dump it outside. It achieves this by allowing multiple indoor units running in heat and cool mode simultaneously from room to room. They also have hydro kits available that can heat water either for drinking for pool or hydronic loops if you wanted to go that route. Geothermal was good tech back in the '90s but with modern systems and controls it's an unnecessary cost in all but the most unique circumstances. As time goes on and technology improves geothermal with continue to be more of a niche technology.

@BrentHull Ай бұрын

wow, ok, thanks for sharing.

@tedkroll9100 Ай бұрын

Why not just use window units? One for every room!

@BrentHull Ай бұрын

Aesthetics for one.

@g1mpster Ай бұрын

Geothermal has been around for decades, and the benefits seem obvious. Why do you think it hasn’t become more commonplace already?

@BrentHull Ай бұрын

Good question. Thx.

@kennixox262 Ай бұрын

I believe that the HVAC industry is slow to change and the fact that most homes now days are production homes; builders are even slower to adapt. They usually put in the cheapest level of HVAC equipment (builder grade junk) and call it a day.

@millardiii Ай бұрын

Serious mis-use of the term Freon. Freon is the trademarked name used by DuPont de Nemours and their successor Chemours for their older refrigerants R-12, R-13B1, R-22, R-410A, R-502, and R-503. Products created by any other manufacturer are not Freon. Newer natural gas based refrigerants are not Freon, even when made by Dupont or Chemours.

@BrentHull Ай бұрын

Thanks for the correction.

@kennixox262 Ай бұрын

I believe that the way the word "Freon" was used in this video was used as a generic term for a refrigerant in a common way that most non HVAC types would understand.