Need help with home water setup. Plus what is the most efficient 120VAC water pump?

the_glassman

My well is being drilled right now and I will need a water pump to supply water for my domestic water needs. My current plans for the house include a Uni-Solar 5kw PVL setup. A Skystream if all the bugs are ever worked out and a net metered grid tied setup.

While DC water pumping originally caught my attention, the extra cost and lack of space for a gravity fed setup with cistern have my thinking about an efficient 1/3-1/2hp 120VAC well pump. The question I ask is which one?

First a breakdown of my water needs:
House is a 3 bedroom/2 bath with open hydronic radiant floor heating on both the basement floor and deck floor. 2000 total square feet.
Toilets will be of 1.1 GPF variety if we can't get approved for waterless composting toilets. Also looking into a grey water recycling system for garden and toilet use.

Shower heads with .5 GPM flow with an Energystar front loading washing machine and dishwasher.


Also interested in going with solar hot water (or DX Geo) setup (cold climate) to provide hot water for home and heating use.

Well will be about 120 feet deep 6" diameter.

So far this is what I've had planned.
120 gallon pressure tank inside in basement from well. (Told to go with the biggest one I can afford) Any recommendations? Also told to get one with a replaceable bladder.

80 Gallon Whirlpool HE electric tank heater http://www.lowes.com/lowes/lkn?action=productDetail&productId=161857-135-EE3Z80HD055V
(Could this act as storage for the SHW and backup for when there is no sun?)

or a solar hot water storage tank with an Airtap heat pump water heater for backup.

So what would be the best pump for this setup? Any other input is greatly appreciated.

icarus

Re: Need help with home water setup. Plus what is the most efficient 120VAC water pu

Couple of quick thoughts? First, I agree with the idea of going with the biggest p-tank, or use 2 or more.

Second, why would you want to use an electric water heater? Unless you are going to use it solely for a diversion load to preheat water that might otherwise be heated with solar or demand propane/nat gas, or even electric demand.

I'll give the pump question some thoughts.

Tony

mike95490

Re: Need help with home water setup. Plus what is the most efficient 120VAC water pu

If the house is not completed, look at a larger storage tank, for hydronic heating in winter, you may need something more like a boiler, than a domestic water heater.

What is the "PVL" in "Uni-Solar 5kw PVL" setup ? AFIK, uni-solar, while good, has a bit of a misleading spec - I believe their panels loose up to 20% power the first year, and continue to slowly degrade. Useful where their non-glass flexibility/ruggedness is needed, but only half as efficient on a sq foot basis.

Look into the "solar shed" as a supplemental collector.
http://www.builditsolar.com/Projects/SpaceHeating/SolarShed/collectors.htm

the_glassman

Re: Need help with home water setup. Plus what is the most efficient 120VAC water pu

icarus wrote: »

Couple of quick thoughts? First, I agree with the idea of going with the biggest p-tank, or use 2 or more.

Second, why would you want to use an electric water heater? Unless you are going to use it solely for a diversion load to preheat water that might otherwise be heated with solar or demand propane/nat gas, or even electric demand.

I'll give the pump question some thoughts.

Tony

I'm trying to go all electric and avoid propane if at all possible. I thought about an on demand, but not sure if it would work with a solar hot water setup. Also they require a lot of power. I figure the tank wont have much if any standby loses as the water will be sitting in a heated space in the basement. I've also been told the advantages of a tankless are diminished when using radiant system.

the_glassman

Re: Need help with home water setup. Plus what is the most efficient 120VAC water pu

mike90045 wrote: »

If the house is not completed, look at a larger storage tank, for hydronic heating in winter, you may need something more like a boiler, than a domestic water heater.

What is the "PVL" in "Uni-Solar 5kw PVL" setup ? AFIK, uni-solar, while good, has a bit of a misleading spec - I believe their panels loose up to 20% power the first year, and continue to slowly degrade. Useful where their non-glass flexibility/ruggedness is needed, but only half as efficient on a sq foot basis.

Look into the "solar shed" as a supplemental collector.
http://www.builditsolar.com/Projects/SpaceHeating/SolarShed/collectors.htm

I originally intended to go with their solar shingles, however they are no longer produced. Instead I plan on going with standing seam metal roofing with these.

http://www.uni-solar.com/interior.asp?id=102

One of the reasons was because of the ease of install, weight and looks.

icarus

Re: Need help with home water setup. Plus what is the most efficient 120VAC water pu

Glassman,

I know little or nothing about radiant hot water especially when tied to solar. As for demand working with solar, demand gas works great. The new generation of demand water heaters are self tempering, so that if the wate is pre-heated going in, it only raises the temp as much as required. I don't know about cost where you live, but grid supplied electric is still more expensive than demand propane on any comparable btu basis where I live. Also if you have to size your grid tied PV for the water heater load,, that get to be a big PV array.

Tony

Solar Guppy

Re: Need help with home water setup. Plus what is the most efficient 120VAC water pu

Unisolar is about 2x the cost of regular Silicon Solar panels and half the efficiency, not a good plan to use the standing seam Asi panels

For what you would pay for the Unisolar 5kW system, you can have 10 kW regular solar panels in the same roofspace and same cost

Solar Thermal hotwater uses about 30 watts to run the cirulator , 5kW vs. 30 watts is a big savings

There is alot to concider, charger controllers, battery banks, inverters ect, if this is your first off-grid project you may find getting professional help a real time and cost savings for this project.

the_glassman

Re: Need help with home water setup. Plus what is the most efficient 120VAC water pu

Solar Guppy wrote: »

Unisolar is about 2x the cost of regular Silicon Solar panels and half the efficiency, not a good plan to use the standing seam Asi panels

For what you would pay for the Unisolar 5kW system, you can have 10 kW regular solar panels in the same roofspace and same cost

Solar Thermal hotwater uses about 30 watts to run the cirulator , 5kW vs. 30 watts is a big savings

There is alot to concider, charger controllers, battery banks, inverters ect, if this is your first off-grid project you may find getting professional help a real time and cost savings for this project.

My state incentives will cover close to half of the cost of the system. It's also much cheaper for PVL install vs racks and panels on my roof.

This is a grid tied system and must be for me to get incentives, so no batteries or anything like that for me.

Solar Guppy

Re: Need help with home water setup. Plus what is the most efficient 120VAC water pu

Racks might add a buck a watt maximum and rebates apply to either Asi ( unisolar ) or Si ( Evergreen, BP, Kyocera ect ) so you get more for you money with regular racked panels.

Get another quote for a racked Si system and then you will have the hard data, but from what I have seen, your looking at close to double using the Unisolar and I have also read one can't even get them ( PVL ) even if you wanted to use them. The PVL has to be installed by Unisolar certified installers or the warranty is voided, so if you do go this route make SURE your installer is approved by Unisolar.

icarus

Re: Need help with home water setup. Plus what is the most efficient 120VAC water pu

Have you considered standing seam mounts? There are some plusses and some minus' to them according to those that have used them, including SG.

PV http://forum.solar-electric.com/showthread.php?t=2777&highlight=standing+seam+mounts Water heat:

http://forum.solar-electric.com/showthread.php?t=2890&highlight=standing+seam+mounts

Tony

the_glassman

Re: Need help with home water setup. Plus what is the most efficient 120VAC water pu

Solar Guppy wrote: »

Racks might add a buck a watt maximum and rebates apply to either Asi ( unisolar ) or Si ( Evergreen, BP, Kyocera ect ) so you get more for you money with regular racked panels.

Get another quote for a racked Si system and then you will have the hard data, but from what I have seen, your looking at close to double using the Unisolar and I have also read one can't even get them ( PVL ) even if you wanted to use them. The PVL has to be installed by Unisolar certified installers or the warranty is voided, so if you do go this route make SURE your installer is approved by Unisolar.

I've got a quote for a racked system, but I'll save that for the solar section.:D

Anyone figure out which water pump I should get?

the_glassman

Re: Need help with home water setup. Plus what is the most efficient 120VAC water pu

icarus wrote: »

Glassman,

I know little or nothing about radiant hot water especially when tied to solar. As for demand working with solar, demand gas works great. The new generation of demand water heaters are self tempering, so that if the wate is pre-heated going in, it only raises the temp as much as required. I don't know about cost where you live, but grid supplied electric is still more expensive than demand propane on any comparable btu basis where I live. Also if you have to size your grid tied PV for the water heater load,, that get to be a big PV array.

Tony

I live in Upstate NY, with some of the highest energy prices in the nation. They are even higher if you choose to have your energy come from green sources. I plan on having the green option for my grid tied system. I really don't want to pay a local propane place to put a ugly tank in my back yard. The pollution between collecting, storing and transporting the fuel is something that weighs on my mind. Not to mention the potential dangerous of including gas into the home environment and potential price spikes and supply problems that could happen someday down the road.

I figure I should come out all right with my net meter agreement with my meter spinning backwards when my home won't be under large loads. We don't get a whole lot of sun, but this house is being built from the ground up to be energy efficient.