Radian or FP2 for whole house offgrid

Re: Radian or FP2 for whole house offgrid

Depending on your appliances, you may need the "big" inverters to start air conditioner compressors or pumps. With the
XW6048, I don't notice anything, except when the 2HP chop saw fires up, then, some of the LED lights will flicker.

Re: Radian or FP2 for whole house offgrid

cdre wrote: »

Planning on an offgrid whole house install with pretty robust loads. Likely around 11kwh/day (refrig, freezer, split unit ACs and a bunch of other loads).

I want as integrated of a system as I can get and was initially looking at an FP2. Wondering now if the Radian may be a better alternative. Everything I read about it focuses on grid-tie, but I wonder if it has any advantages over an FP2 offgrid.

Any thoughts?

We live in Las Uvas, Panama, retired here in December, and have the same thoughts as you, and are in the final design/decision stage for our solar project.

In Panama we have just about a 12 hour split for daytime-night time. Our rainy sea on was supposed to have started in April but it is late and the country is getting nervous because of water levels being so low - over 50% of the power generation here is hydro-electric. the dams are reported to be a few feet above minimum.

Have gone through our load analysis and find that we will use the same power during daytime (0600 to 1800) as night time (1800 to 0600) because of lights and fans. Lights and fans are a huge draw on your resources for off grid. Our stove top, dryer and water heater (hot water on demand) is LPG (butane actually). The load analysis was an eye opener especially when you do actual power readings with a Kill-A-Watt meter. Our energy efficient fridge uses 2.4 kWh/day when the water and ice maker are off, and uses 3.2 kWh/day with them turned on. It is also a black art to try and determine operating times for all appliances, fixtures, etc. How many hours per day will lights and fans be on, will you use the washer every day, do you want to use you coffee machine every day and how many times, toaster, rice cooker (very useful down here - lots of rice), etc. How you live and operate one house may not be how you live and operate another. You won't know exactly how you will live and operate the new house until you are there, and hopefully, your estimate has been close to the mark. Is Mother Nature going to cooperate and provide good natural ventilation?

I have spent countless hours trying to find suitable fans and LED lights at 120 VAC as well. Fridge is not an issue, freezer may be, split ACs are out of the question - 9000 BTU units that I have installed here operate at 4 amps. On 240 VAC this is 960 watts an hour or a whopping 23 kWh/day. You will need generator support to power AC loads.

Still searching for a suitable alternative to the AC issue, no joy so far.

A lot of items here from China, not the best quality, but we work with what we have.

I have found through actual testing that the manufacturers data is the output from an item/appliance, not what has to be put in to get they out; for example, a 6W LED actually uses 7W, your electric toothbrushes at a paltry 1.3W actually will come in around 2.4W. These may be small but they add up quickly. The most efficient non-energy star rated ceiling fan (not many low wattage fans to be had down here - everything is imported) is around 60W without the light. Fans are a necessity down here and to find low wattage units is next to impossible. The Emerson Eco fans are rated at ~20W on high speed. 20W instead of 60W makes a huge difference in your load calculations. The Emerson fans also move twice the air of a standard ceiling fan on high, on medium it moves the same CFM as a standard ceiling fan on high, and at less wattage as well. If you are importing a container, bring them with you. I found an energy star fan (one only) in Panama City. It was energy star because it had a high CFM rating, ~6300 on high speed at 77W, medium speed at ~3200 CFM at 30W (add at least 2W to each power rating- more power in to get the manufacturers output).

I agree with Chris Olson and his stating that a small reasonably sized system with generator support is the way to go. A generator down here is way more economical than bringing in a large battery bank. I can source L16 FLA batteries here in Panama at a premium compared to the US. AGMs are also quite expensive. To ship AGMs here, I have the freight to Florida, then freight to Panama, then duty/taxes, then maybe to our house - money racks up quickly. Bring the generator(s) with you as well, I would surmise that selection where you are going will not be that great.

From comments on the forums, AGMs are nice but since we are down here and importing is expensive, recommend using FLA because with a good maintenance program, you should be able to make them last quite a long time.

24V or 48V system, still in the decision stage on this. Like the comments by Chris that you can use agricultural electrical components with a 24V system. Maybe a consideration where you are going, it is for me. Panama is a great place but it is 30 years behind up north.

For the price of a Radian you could bring two XW4024 24V (I mention these because I have been discussing them with Solar Biz, and folks here) units or equivalent unit(s) in and operate most everything you have and have redundancy. If not and with only one inverter, a generator is a definite requirement, and from what I have gleaned off this web site, not just any generator but one that is matched to your inverter for surge and overload times, pure sine wave attributes, and reliability with a capital "R".

I have found that expertise in the solar arena down here is lacking and that I am really on my own here. I imagine this will be a similar case for you. A smaller system with a good generator or generators is, in my opinion, the way to go. Another issue we have here is that the nationals are always finding stuff that does not belong to them. Talking to the rep at Battery Giant in Panama City and he mentioned that the telecom companies were using 12 and 6 VDC batteries for their remote installations, but are now installing 2V AGMs because the natives were liberating them for their cars - go figure.

As for a packaged system, there will still be a lot of hands on work required to finish the install, and as I have mentioned, expertise in that area may not be as available as one would like. The natives here do not like change, and if they have done something the same way and it has always worked, they are not very open to change.

Our house does not receive any shade until 1700, so installing panels on the roof will have unlimited sun (when it is out) all day long. Lots of sun here as well, but some houses have way too much shade (shade equates to cooler temperatures), or more shade then one would want for a solar installation.

If you are considering a solar installation, you are probably going to consider a water system as well. Water pumps have huge power draws on 120VAC. You could consider using a 24V or 12V water pump - similar to a boat -to provide the pumping for your system, unless of course it is a well pump. An option could also be to pump water into a storage tank and use the storage tank as your primary then a 12 or 24 VDC system would be appropriate.

The pre-packaged system sounds great. Looked at these and the price is higher than a system that is pieced together by a reputable company. I have been in discussion with Solar Biz because it has a dealer here in Panama (system is imported from the States) and the quoted system from them - non-packaged - is apparently a complete system, just have to be installed. from what I can see there is only some cabling to be bought, or extras that I want. On this note I just want to say that nothing is plug and play, and that you may be able to get a non-packaged system that would be comparable to a pre-packaged system at less cost.

i am no expert but my learning curve has been exponential in the last few months.

My $0.02 FWIW.

Cheers, good luck on your new adventure, and have fun.

Cheers

Ernest

Re: Radian or FP2 for whole house offgrid

cdre wrote: »

...... For water, I'll be harvesting rain and expect to set up a few pressure tanks with 120v pump. I haven't yet done a ton of research on the most efficient pumping options....

You may want to consider the pro/con of 120V & 240V pumps. For running off inverters, there are 2 wire & 3 wire motors, and the 3 wire motors are a bit less hungry for starting surges. Surface water or well ? How do you filter the water & keep it pure?

Re: Radian or FP2 for whole house offgrid

cdre wrote: »

Ernest,

Thanks for the detailed reply. In Belize I currently have a 300w 12v system on a trailer and I'm about 2 years away from construction on the house. I'm sure available options will change between now and then, but staying abreast of developments in the space and planning is a little bit of a hobby right now I guess.

I'm shipping everything through Florida as well, so not counting too much on local suppliers for key components. Looking at doing a packaged system because there isn't a ton of solar expertise locally. I want to make installation as straightforward as possible.

For water, I'll be harvesting rain and expect to set up a few pressure tanks with 120v pump. I haven't yet done a ton of research on the most efficient pumping options.

Still lots of planning to do, but this forum has been an invaluable source of experience and info.

Another issue that we had to deal with is how the houses are built down here. Being cinder block construction, I had to try and envision how the electrical circuits would be laid out. There was also the issue of having everything installed in the walls and floors in conduit, including the electrical panel. This limits any changes down the road after everything is completed. I did insist that the electrical panel and the conduits to it were outside the walls in a small closet. had some resistance but it was done because I wanted it. It also allows you to mix and match as you configure your solar system. As the phrase goes: it is cast in concrete.

Hindsight is 20/20, and in retrospect, I would have insisted that the outside plugs were on its own circuit, kitchen outlets as well. The electricians down here like to use 20 amp circuits for everything, with the corresponding 20 amp wire. The workers also can't understand why we would want certain things when the way they do, and have done it is perfectly fine. My builder simply tells them that that is what I want, just do it.

We are also having insulation put in the attic, keeps heat out of the inside as well. I have had to insist on roof vents as well as the workers down here do not think they are necessary. I am also of the mind that a house off the grid down here because pif the heat could benefit from installing 1/2 inch insul board to the exterior walls, then attach wire mesh and large over. A cinder block/concrete house is a large heat sink.

When you build, make sure you have conduit in the walls where you would like to run the panel wires to the solar control station. I will have to have mine installed after the fact. The workers will grind out a channel, install the conduit and parge over it, never know it was done.

When you plan your solar control station, if it is in a workshop separate from the house, plan on running a couple of conduits from the where the electrical panel in the house is to the outside wall nearest to where your system is for AC wires into the house and control cabling for monitoring the system. Inside the house try and determine where it would be best to put a monitoring station and have conduit put in place to accommodate this. It's not impossible to do this after the fact, but it is messy. Once the conduit is in you can easily "fish" your cables through.

I will be looking at a backup generator and one for generator support. Probably have the backup generator first as it will be the least expensive and easiest to source here. Also let me keep the batteries charged when needed.

For your water, source out a filtration system in the US. More choice there, and you will need it. For a water pump, the Groco Paragon pumps are the cadillac of marine water pumps, comes in 12V and 24V models, and expensive (but the best at ~$2700.00 for the 12V and ~$2800.00 for the 24V). Self-priming up to 10 feet.

Just some more info.

Cheers

Ernest