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Google spinoff Dandelion uses ground energy to heat and cool homes

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Re: Google spinoff Dandelion uses ground energy to heat and cool homes

#31
While Dandelion is the flashiest player in the Geothermal space right now because of their relationship with Google, they really aren't offering too much innovation inside the industry where some really exciting things are happening.

For example, there is startup, Geothermal Drilling Solutions [1], that is, in my opinion, poised to disrupt the entire industry.

Their website isn't great, but from what saw and heard from them at a recent conference, they have a rig that can drill in the basements of existing structures. They are going to bring geothermal to major population centers where it is otherwise impossible, and I'm hopeful from the demo I saw, do it faster and cheaper than "traditional" drillers like Dandelion.

[1]: https://www.geothermaldrillingsolutions.com/

Re: Google spinoff Dandelion uses ground energy to heat and cool homes

#32
The EER on their ground source heat pump is abysmal.

For a 4 ton pump, they have 17.5 EER, 3.9 COP

For the O(same price) for the unit, the waterfurnace 7 series is 41.0 EER, 5.3 COP.

(Both can provide all hot water, etc).

The waterfurnace also carries a 10 year warranty instead of 5 year labor/10 year parts.

Can't speak to the drilling rig, which also seems interesting.

Re: Google spinoff Dandelion uses ground energy to heat and cool homes

#33

Dandelion Air is a geothermal system that moves heat between the house and the ground using plastic pipes and a pump -- bringing heat to the building in winter and pushing heat to the ground in summer. So what we've been putting in homes for ~40 years already. Thanks Google!

My local well drilling guy has offered "geothermal" for years (decades?) Despite a large inventory of wealthy second home owners, he didn't get and still doesn't get many takers. Meanwhile, rooftop solar is everywhere. My parents almost bought their "retirement home" with an existing geothermal system - it remains the only "real world" home instance of this technology that I have encountered. $20K also seems very clo…

FWIW: I had geothermal in my house in maryland, and loved it. The system consistently beat the listed performance specs, which were detailed and complete and easily findable. See the submittable data at https://www.waterfurnace.com/residential/products/literature

This is compared to air heat pumps, where they give you a single number with no factors, and your system rarely will get that number given your set of variables. You can get the full performance sheets if you nag the crap out of them or you are a contractor and have access to the service site.

It is significantly more common in areas on the east coast (which has a good climate for it) and also areas where wells need to be drilled anyway.

It's less common in areas with city water/sewer.

When i talked with the well drillers, they were doing a bunch of residential geothermal installs each week, so ...

Re: Google spinoff Dandelion uses ground energy to heat and cool homes

#34
post #22

Earlier quoted context omitted.

My local well drilling guy has offered "geothermal" for years (decades?) Despite a large inventory of wealthy second home owners, he didn't get and still doesn't get many takers. Meanwhile, rooftop solar is everywhere. My parents almost bought their "retirement home" with an existing geothermal system - it remains the only "real world" home instance of this technology that I have encountered. $20K also seems very clo…

I wonder, how "compatible" this is with solar. I.e. if you install solar by itself, you save X dollars/month. If you install this by itself, you save Y dollars a month. If you install both, is it close to X+Y, or is there some substitution there? On one hand, you can sell solar back to the grid, but you can't always sell it back at retail, so I would guess your savings would be smaller, but how much smaller? Or would…

Depends on how you heat.

If you live in a climate where you need to heat in the winter and cool in the summer, ground source heat pump are cheaper to operate than oil, gas and A/C. Solar will contribute to reducing your A/C electricity bills and also all the other power you use year-long, so they work together.

If you live in a climate where you occasionally turn on an electric heater for those really cold days, this will only help during cooling season, while solar will contribute all year long.

Re: Google spinoff Dandelion uses ground energy to heat and cool homes

#35

While Dandelion is the flashiest player in the Geothermal space right now because of their relationship with Google, they really aren't offering too much innovation inside the industry where some really exciting things are happening. For example, there is startup, Geothermal Drilling Solutions [1], that is, in my opinion, poised to disrupt the entire industry. Their website isn't great, but from what saw and heard fr…

Most cities don’t include adequate ground-depth rights in land titles, so home-scale geothermal in cities is almost certainly out. This isn’t a regulatory thing; you literally only own the first 10 feet of ground or so (hence so many horizontal geothermal systems).

Should play pretty well in the suburbs, where oil heat is more common.

Re: Google spinoff Dandelion uses ground energy to heat and cool homes

#36
post #12
post #2

There doesn't appear to be anything new about this, ground-source heat pumps have been available for domestic use for quite some time. And going by the name, and looks, it's actually an air-source heat-pump, but I could be wrong.

Dandelion uses a cheaper drilling method to reduce up-front costs. https://blog.x.company/introducing-dandelion-2706eded169a

Well, that is what they say (without telling anything about the actual drilling method).

A typical water well drilling machine is on the back of a large truck and will bore a 30-40 cm hole for (prices here in Europe) 80-90 €/m.

There are smaller drill rigs (nothing that actually needs to be invented, only "normal" micropiling rigs) that can bore 10-20 cm diameter holes for a price of 60-70 Euro/m.

Let's say you need two holes 80 m deep, at 20 €/m difference (80-60=20 or 90-70=20):

28020=3,200

which represents roughly 10% of the actual price for the dandelion system (the real, not subsidized price) of 35,500 US$.

A typical small micropiling rig has a boring rate of around 100 or maybe 120 m per day so either they are really using a new, ultrafast technology (which I personally doubt) or are using less deep bores, and in any case the depth depends on the geology of the site, so everything is probably "averaged".

A geotermic pump with inverter with 20-30 kW of heating/refrigerating power should be around 15,000-18,000 € so, without more data 30,000 € or 35,000 US$ don't seem such a breakthrough (most probably they have huge savings due to the "massive" scale of operation, instead).

Re: Google spinoff Dandelion uses ground energy to heat and cool homes

#37
post #25

Earlier quoted context omitted.

I'm curious how much this affects the price. I'm not a homeowner any more, but when I was, I longed to replace my furnace with a ground-source heat pump. It is not too much of an efficiency win over gas for heating, especially since we used little heat, but it's great for cooling. But I was really put off by the price. There was no way to justify it even under the most pessimistic assumptions about energy prices, exc…

I think cost is the biggest issue. If you want to reduce heating and cooling costs via investments then insulation + solar can cheaply make a huge difference. Ground source scales well if you have a large building and a large body of water near by then the payback time is short. But at single family home level it's just not that useful.

That's not what my analysis showed. It has a payback period of 5-10 years depending on your assumptions, assuming new construction. Shorter period the more extreme the climate, longer in places like Norcal. Retrofitting though is a different story (higher cost -> longer payback).

Re: Google spinoff Dandelion uses ground energy to heat and cool homes

#38
post #6

Misprint? Commonly available ground source systems can save upto 75%. That's way ahead of the article's claimed 20%. At 20% it's simply not worth the cost of installation. Dandelion's website won't load to let me check.

The EER/etc on their pumps is just horrible.

Re: Google spinoff Dandelion uses ground energy to heat and cool homes

#39
post #35

While Dandelion is the flashiest player in the Geothermal space right now because of their relationship with Google, they really aren't offering too much innovation inside the industry where some really exciting things are happening. For example, there is startup, Geothermal Drilling Solutions [1], that is, in my opinion, poised to disrupt the entire industry. Their website isn't great, but from what saw and heard fr…

Most cities don’t include adequate ground-depth rights in land titles, so home-scale geothermal in cities is almost certainly out. This isn’t a regulatory thing; you literally only own the first 10 feet of ground or so (hence so many horizontal geothermal systems). Should play pretty well in the suburbs, where oil heat is more common.

You're right that does prevent some drilling depending on the city and it is a shame as it locks out a lot of downtown properties. I'm also not a big fan of horizontal systems and prefer vertical fields whenever possible.

Still, I'm excited because I think there is a big market for residential and commercial spaces that don't have the footprint or alley access to fit a conventional rig.

Re: Google spinoff Dandelion uses ground energy to heat and cool homes

#40
post #36
post #12

Earlier quoted context omitted.

Dandelion uses a cheaper drilling method to reduce up-front costs. https://blog.x.company/introducing-dandelion-2706eded169a

Well, that is what they say (without telling anything about the actual drilling method). A typical water well drilling machine is on the back of a large truck and will bore a 30-40 cm hole for (prices here in Europe) 80-90 €/m. There are smaller drill rigs (nothing that actually needs to be invented, only "normal" micropiling rigs) that can bore 10-20 cm diameter holes for a price of 60-70 Euro/m. Let's say you need…

Does it really need to go 80m deep? Seems like a very deep hole

They're probably looking at a width of 10cm tops from their description.

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