New member here - I have been reading posts for literally days trying to get a handle on the best option for our new home.  We are right at the finish of our design phase and will be breaking ground shortly.

Details:  Home will be stick built with 2x6 exterior walls, mostly flat roof with 2 sections of metal sloped roof R30, slab on grade with 2" foam under slab, total heated 2700 sq. ft, reverse floor plan - all bedrooms are downstairs, warmboard upstairs, open floor plan upstairs. Hydronic radiant in floor heat planned. Natural Gas is available.  We have lots of south and west facing roof space with zero or limited shading, but they will be flat roof zones.  We are in climate Zone 3 with 1400 HDD per year - a coastal climate with lots of fog in summer, afternoon sun is common most days.  No cooling needed.

We currently have a Lochinvar KBL150 boiler for DHW and Radiant on our preliminary plans based on the energy calculations that were run, but in reading many other posts here I have a few other ideas that I thought might work but - of course many here are in much colder climates it seems, so it is hard to get a feeling for what would work for our situation.

So here are the options and help we need - keeping in mind that we would like to get a system that is ideal for our location and has the lowest cost up front and operating.

1. Use a single boiler (or equiv) as specified and just run with it...
2.  Use a smaller boiler - say a Lochinvar 50 along with an indirect hot water tank - running the radiant heat with glycol instead of shared hot water - plumb for future passive solar hot water to the indirect tank.
3. Use a hybrid electric water heater and connect with PV system (may not work as our DHW and heating needs are mainly in the eve and early morning)
4. Something else recommended by others here...

Let me know what your ideas would be, and if I can provide other information - thanks in advance!

What is your electric and gas cost and do you want to assume they will continue to be available and increase in cost same as they have for 20 years?

Do you have any additional utility or state incentives for renewable energy?

How many family members and are you on the East or the West?

We are on the West Coast - Northern California, so PG&E, family of 3 - 2 adults, 1 child.

January Electric Costs: $.12 Kwh up to baseline of 565 Kwh $.13 at 101-130%, $.29 at 131-200% baseline (don't expect going much over 130% range in this new home)
Gas last bill: ~ $0.98 to $1.08 per Therm

I am assuming they will rise slightly over time - I don't anticipate large increases

There are some incentives for renewable energy in state rebates (wind turbines, and fuel cells)

I don't have all of the Solar rebates researched yet, plus they are running out of money it seems in some programs...

Another note - PG&E offers rebates, but for Retrofits only...so I could put it up after the home is built, so I am thinking of pre-wiring and pre-plumbing for "future" solar...