Whole House Generator vs. Hybrid System

[chuckb]

Hybrid Systems

Several times of 8+ days, I would be interested in the approximate area of the world you are located?

I live in Southern New Hampshire and averaged 6-9 days a year without power for the past four years. The longest single outage (13 days for an ice storm) was in 2009 before I moved to NH. We frequently have 3+ day outages. That is what happens when you live in a small rural town on the edge of of the utility's network. It is also a wonderful place to raise three small children and care for two elderly grandparents. We have no plans of moving any time soon.

I have a propane powered 12.5kW Generac (burning 1.6gph) installed by the previous owner that is 8+ years old. I plan to replace it with a Kohler when it is no longer repairable, but hopefully not for the next couple of years. I also have a manual 6.8kW gas generator as a backup. I have a 500gallon under ground propane tank that serves heat, cooking, DHW and the generator which powers the well water. My heating is ~650W of circulating pumps and a propane boiler. I previously moved all of my generator-backed loads onto a dedicated panel and feed that from the ATS in preparation for this solar project.

I am currently looking at my options for DIY solar installation. I am heavily leaning towards 8.5kW of SolarWorld (26 @ 315W) panels with an 8kW Outback Radian inverter, AGS and a 48v ~300A AGM battery bank for roughly $28k before rebates. Our monthly consumption is around 1400kW/h. That price includes equipment, assistance with racking and mounting, and me performing all electrical work (NH allows the homeowner to do this and I have a good background to do it safely). I am also considering adding a small (~40A) 120v battery charger that I could run off a quiet, fuel sipping, Honda EU2000i.

If I am going to do solar, I think it makes sense to have some battery capacity for the longer term outages. I don't like using my heating fuel to run a large generator 24/7 which is why I have the gas backup. However, I frequently travel for work and need something that can be automated. During the coldest months, we can go through 300+ gallons of propane in a month. Pick the wrong time of the month for a power outage, close roads stopping propane delivery and... At most times during an outage, our consumption can be low and the loud generator is still running. The wonderful feeling you get when it starts automatically goes away after the first day or so. Energy rates in NH have been going up and generation costs are predicted to go up as much as 30% over the next four years.

So that's my idea and a little bit of the situation. Any feedback is welcome before I write a check. Tell me I'm crazy, doing it wrong, using the wrong equipment, wrong supplier, etc. Or tell me I'm on the right track. Thanks in advance for any wisdom you can share.

[solar pete]

Hi All,

Very interesting thread, just wanted to chime in re hybrid system. To me the value of the hybrid system is two fold and needs to been seen as such. Firstly the properly designed and installed hybrid system (now I am speaking with Australian rules and regs in mind, i know things change a bit depending on where you are) allows you to charge your batteries during the day while the house hold is out at work/school and use your battery power at night time.

To me in SA at least (we have very high electricity prices 30cent kWh to 40 centskWh) this is the real beauty of the hybrid, yes it also gives you a back up when the grid is out but we have a relatively stable grid, we are going to install a very large hybrid system at my brothers (he owns a solar install company in SA) soon and when he eventually makes up his mind on batteries and inverters, cc etc I will post some info and pic's, the 20kW of panels are up and the battery bunker built but that's as far as its got so far. Cheers

[sahucker]

approximately location?

....Our area has had power outages of 8 days or more several times in the past few years due to weather events. ....

Several times of 8+ days, I would be interested in the approximate area of the world you are located?

[Willy T]

Chris Olsen, the King of Off Grid Living.

Well, I've been busy here. Like I said, I got new projects going that is outside the scope of "renewable energy" forums, so have little time to participate. When our present battery bank wears out we will not be buying another one. I've designed and built a dual redundant, failover co-generation CHP setup using 900 rpm diesel power that will be replacing our present system this coming summer. I can put the entire system in for less money than what it will cost to replace our present batteries in a few years. I have the first unit built and tested and sitting in my shop. It has a Cummins 4BT power unit. The units are 25 kVA prime, each. I'm building a second unit for redundancy and peaking - have it about half done right now and trying to get it done before spring. It took me 2 1/2 months to build the first one. I'm hoping to have the second one done by April so we can fire up the excavator in the spring and start construction on our new power plant.

The XW inverter is "smart" enough, has AC coupling capability, and has good enough controls and monitoring to be able to use it as the "grid" and "brains" for the system to tell the Cummins Power Command system how to control and sync the CHP units. We will have full 200A service to both our house and my shop when I get it done.

Our new system will eliminate having to burn wood for primary heat, provide us with virtually unlimited power with totally automatic control, used staged generators to cut fuel burn when only one is needed, and eliminate the expense and headache of batteries. Sure, it's not really "going green". But I could care less about "going green" except when it comes to saving green on off-grid power costs. And the type of system I have designed is in common use in remote Alaska villages and South Pole Station in Anarctica for many, many years. The US becoming the largest oil producer on earth pretty much made so-called "going green" obsolete as far as I'm concerned.

[russ]

I agree with you that having a plan to live without power is more important than backup power, due to risk of EMP, which will may or may not happen in our lifetime, but will likely happen someday. Yep - if you watch the fruitcake TV shows it could happen any day

"being prepared for a world changing event is a waste of energy, time and money" is one of the most foolish comments ever spoken. The way you put it throws it into the stupid section

I produce 100% of my power, don't use any nat gas or LPG and did not spend a lot of resources to get there. The materials are not that expensive, just need to be knowledgeable enough to correctly install yourself and navigate government obstacles.

That is 3$ worth pf BS in a 2$ bag

[SunEagle]

I am not trying to convince folks to prepare for long term outage, although you are telling folks that is a waste of time and money, not sure why you think you get to determine what is waste of other peoples time and money, seems like it is their time and money. People that can not afford food are not the folks installing solar systems. I agree with you that having a plan to live without power is more important than backup power, due to risk of EMP, which will may or may not happen in our lifetime, but will likely happen someday.

"being prepared for a world changing event is a waste of energy, time and money" is one of the most foolish comments ever spoken.

I produce 100% of my power, don't use any nat gas or LPG and did not spend a lot of resources to get there. The materials are not that expensive, just need to be knowledgeable enough to correctly install yourself and navigate government obstacles.

Oh I agree the chance of an EMP is possible. For that matter so is a magnitude 11 earthquake, an X12 solar flare, large celestial body impact, financial system melt down, Virus Pandemic to name a few.

If you already live remotely and are totally self sufficient then you might survive one of those cataclysms. But for the majority of the US (myself included), life expectancy will be very short if any of those events happen. I would rather not spend the time and energy now worrying or preparing where I will get food and water to survive each and every day of my remaining life. I would rather enjoy my life now with my family and get the most out of it because I can't stop any of those events and I sure don't want to try to live through one.

[sulfur]

I am not trying to convince folks to prepare for long term outage, although you are telling folks that is a waste of time and money, not sure why you think you get to determine what is waste of other peoples time and money, seems like it is their time and money. People that can not afford food are not the folks installing solar systems. I agree with you that having a plan to live without power is more important than backup power, due to risk of EMP, which will may or may not happen in our lifetime, but will likely happen someday.

"being prepared for a world changing event is a waste of energy, time and money" is one of the most foolish comments ever spoken.

I produce 100% of my power, don't use any nat gas or LPG and did not spend a lot of resources to get there. The materials are not that expensive, just need to be knowledgeable enough to correctly install yourself and navigate government obstacles.

[donald]

A three month outage in the U.S. is very unlikely. If the power is out that long, it's probably not coming back on. I would offer three weeks as the max for planning purposes. Over 10 days would only be for isolated properties.

With a generator, in a potentially long term outage, power probably shouldn't be produced 24/7, even with fuel available. Eat the frozen food first. Make ice during the day to carry the fridge overnight with the power off.

My sister was out for 10 days a couple years ago as a result of the new england fall snow storm. The service line was down on her property. I think the last isolated property in CT was put back on the grid after about three weeks.

In my experience having 1500-3000 watts available to use 8-12 hours per day is about 95% as good as having full power. In cold weather areas, the minimum backup power requirement should probably be what is needed to start the motor on the furnace.

[SunEagle]

If grid was out for 3 months, propane would certainly also not be available. Having solar power would be very important to keep my well running, to keep freezers running, that is "real". Some people get solar to save the planet, some get solar to be self reliant. Those who want to save the planet and want backup power should get a generator, those that want to be prepared should have a solar system that can run off grid. That giant generator she was suggesting is not great for longer term outage, as we all know, but your correct that it could be conserved to some extent. Your lets be real here comment is a snarky comment that apparently makes you feel better because you are not prepared for much of anything.

So how often has the grid gone out for 3 months for anyone? Being prepared is one thing (which I am in the case of hurricane damage and short outages) but being prepared for a world changing event is a waste of energy, time and money.

Getting water out of a well has been done for centuries without any electric power and keeping food frozen will not keep you from being hungry. Food preservation processes do not always require keeping it "cold". How long do you think medical supplies will be available without power.

If you want to be prepared for a long duration power outage then you better learn to live without it now and not spend resources trying to make sure you can generate it long after it is gone.

People who live in 3rd world countries will survive longer without power than most people in the US since we have been babied with technology and cling to it on a daily basis.

You can do what you feel is necessary for you and your families well-fair but please don't try to convince others that they need to follow your path.

Most people don't have enough money to pay the bills and keep food on the table let alone spending it to be "prepared".

[gardner]

If grid was out for 3 months [...] Having solar power would be very important

An event that caused a 3 month power outage would probably blow the solar panels to Cuba, not to mention flatten the home. A generator shed is a lot more weather proof than 500 square metres of panels.

[sulfur]

If grid was out for 3 months, propane would certainly also not be available. Having solar power would be very important to keep my well running, to keep freezers running, that is "real". Some people get solar to save the planet, some get solar to be self reliant. Those who want to save the planet and want backup power should get a generator, those that want to be prepared should have a solar system that can run off grid. That giant generator she was suggesting is not great for longer term outage, as we all know, but your correct that it could be conserved to some extent. Your lets be real here comment is a snarky comment that apparently makes you feel better because you are not prepared for much of anything.

[SunEagle]

The point of my comment is that if she is trying to protect herself from long term outages, say 3 months, she will not have enough propane and will have no power. Just depends what the goals are.

Let' be real here. If there is a power outage that lasts 3 months not having electricity will be a very low priority for me and most people.

A power outage for weeks is possible and survivable with some proper planing and conservation you could stretch a fuel source to meet the necessities. I would be more worried about having clean water and food.

And having power from solar and batteries while all of your neighbors go without is like a sign post for thieves.

[russ]

The point of my comment is that if she is trying to protect herself from long term outages, say 3 months, she will not have enough propane and will have no power. Just depends what the goals are.

Maybe shw could buy more propane? If it is not available then that would be the least of problems.

[sulfur]

The point of my comment is that if she is trying to protect herself from long term outages, say 3 months, she will not have enough propane and will have no power. Just depends what the goals are.

[SunEagle]

when making your decision about hybrid vs generator, consider how long of an outage you want to protect yourself from, if only a week, then generator is cheapest route, if you want to protect yourself from longer term grid outages, then 2 Sunny Islands and several batteries may be appropriate, Sunny Islands only put out 120VAC plus you seem to want capability of lots of watts. You can use 2 SI for 240VAC or use one SI with a step up transformer.

I wouldn't use the length of an outage or even the number of outages a year to justify between using a generator or battery system.

A generator that is properly exercised and maintained will still be available and useful if it has been used only once for an extended period or 10 times for an extended periods after 5 years.

Batteries on the other hand, used only once or every day will be near death after 5 years and need to be replaced.