Solar energy just for your reef tank: Have you thought about it?

[revhtree]

Have any of you considered going solar for just your reef tank? Is this something that is even feasible? I must admit I have zero knowledge about this topic so educate me!

Also how much energy is your tank consuming monthly?

 

[redfishbluefish]

I did look into it about 3 - 4 years ago. NJ has/had very good rebates deals, so made the payback that much quicker. The negative for me is that they wanted me to take down the one and only tree that shades my house. I also had roofs that faced east/west...still would work, but ideal is a south facing roof. So decided not to do it.

Here's the bottom line....and again NJ has/had some very nice rebates...check your States rebates. Here's the important part, outright buy your panels. Yes, you'll have to spend 10's of thousands of dollars, but all the rebates and benefits will go to you. What is very popular now in NJ are these companies that will give you panels at no out of pocket for you. You will initially get a small reduction in your electric bill, but are not entitled to the rebates (they go to the company that installed.) Eventually you will most likely end up paying more for electric as the years go by.

Highly recommend doing the math for your State to see if it will pay in the long run.

 

[EmdeReef]

If you’re just looking for panels to just run the tank then getting enough to cover your lights, potentially chiller, if you run one, is all you need to cut down the electric bill (maybe heaters if a big difference from ambient temp). You would need a good battery too.

Something like the below would likely be enough for most LED lights. If you get 2 and a good battery then can probably run most of the tank. Have to assume lower than 100% efficiency and on some days depending on the season and where you live can drop significantly I think I was told as low as 10-20%. Someone with better electrical knowledge can weigh in about what equipment is needed to automatically switch between the two sources of power. But most likely looking at 2-3k investment.

https://www.amazon.com/Renogy-2Pcs-...olar+panel&dpPl=1&dpID=41dHnXshhXL&ref=plSrch

 

[sde1500]

I wouldn't see the point of setting one up solely for the fish tank, but I have priced out a system to run the whole house. Decided to push it back a few years as other projects are more important. In the mean time hoping battery prices fall a lot more. That is where it really would be worth it. Not just running on solar when it is sunny out, but having enough of a battery back up in place to run 24/7/365 on the power you produce and store. Anyone looking into it, energy sage is a pretty good resource to use.

 

[User1]

Solar - works. However, the panels we consumers use are not really low earth orbit / space station equivalent yet. So that sort of puts a damper on the overall generation and return on investment. As noted above the rebates are what helps the home owners (aka local, state, or federal tax credit). Small panel for the tank isn't something I would even remotely consider - the return isn't there.

However, panels on the roof are somewhat there and depending on your daily solar generating window then it may work out ok. I'm in California and when we downsized our home about four years ago the builder got an amazing deal on solar for his development. That along with federal tax credit our return on investment was about 5 years to break even. We are seeing the benefit now of course but looking at what I paid upfront and monthly math put us at around 5 years.

In any case solar panels need to be better before production is really self sustaining for home users. Depending on who you use we are talking a range of 14 to 23%. Do some math and you can see the disparity in the power generation of panels. Buyer beware at the end of the day. Once the panels get higher efficiency and product more - say 40 - 50% then we are talking. Sadly those panels are not here today and the ones that are in the 20% range are more expensive...

We need more RnD time to lower the costs with a bit of regulation change to make that happen. Getting there but my guess is another 5 years. Then the battery store similar to what Tesla produced (one that actually works) along with high production solar panels then we will have a green home.

 

[User1]

Forgot to add to my post, sorry.

Controller - Apex power bar isn't too bad at measuring use.
Kill-o-watt meter - is a cheaper solution and may shed some light if you are sleuthing to lower costs.
Sense - a device to add to your main panel and uses AI to find things in house and will monitor use, cost, etc. I have one, nerdy and nice also does solar
TED - similar to Sense but connects to breakers instead
Math - read the label and use excel - gives you high end numbers
Electrical bill - doesn't drill down but total monthly costs

There you go. I use solar and also Sense monitor. LED lighting and return pumps (debate on what that actually saves). Apex power bar gives me an idea.

 

[Coralmaniac21]

My tank is in the front of my house... which gets sun all day long.. but thanks to an association we cant install solar panels..

I want to move so bad.. never again with assocoations... i love how they csn tell you what to do with a house you own and pay bills on..

 

[pickupman66]

I would not dedicate solar to my tank. the return on investment is just not there IMO. in my area, i would need battery to be able to supply up to 500 watts and last for multiple days without recharge as we have some time here with all clounds and rain.

 

[Rybren]

I have an off-grid cabin that it is powered by solar. Solar works, and could easily work as a stand-alone system for your tank. It needn't be overly expensive, but would likely take years to pay itself off.

Start by getting yourself a Kill-a-watt meter. (You can often borrow them from a library) Plug your tank into the meter and monitor your usage for a few days or more. From this, you will be able to determine your energy usage in amp-hours (AH). You will use your daily amp-hour consumption to size your battery bank.

For example, if your tank uses 100 AH daily, and you want to be able to run your tank for 3 days off the system (to account for bad weather/no sun days), then you would, in theory, need a battery bank capacity of 300AH. However, most people use flooded lead-acid deep cycle batteries, and you generally don't want to run them below 50%, so you'd need to double the capacity to 600AH.

Once you've decided on a battery bank, you'll need to determine the size of the solar array required to charge them. A general rule of thumb is that the array will need to be able to produce enough current that equates to roughly 10% of the battery bank capacity (in our example, that would be about 60 Amps.) This would require roughly 2400 watts of solar panel. An array of this size has a fairly large footprint.

You'll also need a decent charge controller to take the energy from the panels and charge the batteries, and you'll also need a pure-sine-wave inverter to convert the DC current from the batteries into AC current.

A system of this size could be DIY'd for $7-8K. Note that it would be totally independent of your existing household electrical system.

You probably wouldn't need a system this large, but it will give you an idea of the steps required to plan it out.

 

[User1]

I have an off-grid cabin that it is powered by solar. Solar works, and could easily work as a stand-alone system for your tank. It needn't be overly expensive, but would likely take years to pay itself off.

Start by getting yourself a Kill-a-watt meter. (You can often borrow them from a library) Plug your tank into the meter and monitor your usage for a few days or more. From this, you will be able to determine your energy usage in amp-hours (AH). You will use your daily amp-hour consumption to size your battery bank.

For example, if your tank uses 100 AH daily, and you want to be able to run your tank for 3 days off the system (to account for bad weather/no sun days), then you would, in theory, need a battery bank capacity of 300AH. However, most people use flooded lead-acid deep cycle batteries, and you generally don't want to run them below 50%, so you'd need to double the capacity to 600AH.

Once you've decided on a battery bank, you'll need to determine the size of the solar array required to charge them. A general rule of thumb is that the array will need to be able to produce enough current that equates to roughly 10% of the battery bank capacity (in our example, that would be about 60 Amps.) This would require roughly 2400 watts of solar panel. An array of this size has a fairly large footprint.

You'll also need a decent charge controller to take the energy from the panels and charge the batteries, and you'll also need a pure-sine-wave inverter to convert the DC current from the batteries into AC current.

A system of this size could be DIY'd for $7-8K. Note that it would be totally independent of your existing household electrical system.

You probably wouldn't need a system this large, but it will give you an idea of the steps required to plan it out.

And this brings us back to panel efficiency

Edit: good post btw.

 

[Rybren]

Yup. Most panels are in the 17% efficiency range.

One thing I failed to mention is location. In my area, because the winter daylight days are so short, a generator is usually required to charge the batteries because the solar panels can't keep up.

In my case solar was the only viable option - the cabin is remote and the local utility wanted close to $100K to bring in power. My solar system cost $5K

 

[Brew12]

I figure my tank has an average demand of .6 kW and a peak of 1.5kW. 0.6kw demand would be 0.6kwh*24hours*30.3 days. So, my tank uses roughly 436kwh per month at a cost of $.08 per kwh for $35 per month. It would be hard to get payback on it for me.

 

[Gareth elliott]

I briefly looked at this as like @redfishbluefish also live in new jersey. But have had several friends selling their houses and the part that took the longest with finalizing the sales were the solar lease agreement. Think what would really give me pause was to make sure i went with the correct installation and company.

 

[User1]

I briefly looked at this as like @redfishbluefish also live in new jersey. But have had several friends selling their houses and the part that took the longest with finalizing the sales were the solar lease agreement. Think what would really give me pause was to make sure i went with the correct installation and company.

I think solar leases are a waste and a rip off. Buy it out right so you get the benefit otherwise the lease owner is getting the tax credits and you are getting little.

 

[andrewkw]

For me it would only make sense if I went completely off the grid. I moved to Northern Ontario a couple of years ago and everyone here complains about how hydro (electricity) rates. Turns out rates here are the same as Southern Ontario, the only thing different is the delivery charge is high. Sometimes my delivery charge is as much as $100, yet my total bill rarely exceeds $300 and is often in the $200 range. This is with 4 reefs and some other stuff that takes lots of electricity. Of course I don't have central air but the portable ac does use quite a bit. The funny thing is I often here horror stories of people (non reefers) have $1000+ bills ect and I wonder what the heck are they doing and how inefficient is there house.

You gotta be pretty sure you plan on staying long term to make this step. Initially when I bought this house I thought I'd be here forever, it didn't take very long to decide I can't wait to move again. Hopefully the next place will be more long term and I'll revisit solar then, but the way things have been going with less government incentives, unless the price of electricity substantially goes up I'll just keep paying the monthly bill.

 

[OriginalUserName]

It would be difficult/costly to power just your tank along on solar. Now, if you are talking about installing a system for your home to offset the energy costs, yeah, depending on your geography and local incentives.

My ultimate goal is to do home solar with some battery backups (probably Tesla powerwalls). Then I'd be saving money on power and giving myself power outage security without dealing with a generator. I'll need a new roof in 5 years so I'm hoping the Tesla solar roof tiles are fully rolled out by then (and hopefully a little cheaper).

Forgot to add to my post, sorry.

Controller - Apex power bar isn't too bad at measuring use.
Kill-o-watt meter - is a cheaper solution and may shed some light if you are sleuthing to lower costs.
Sense - a device to add to your main panel and uses AI to find things in house and will monitor use, cost, etc. I have one, nerdy and nice also does solar
TED - similar to Sense but connects to breakers instead
Math - read the label and use excel - gives you high end numbers
Electrical bill - doesn't drill down but total monthly costs

There you go. I use solar and also Sense monitor. LED lighting and return pumps (debate on what that actually saves). Apex power bar gives me an idea.

How much of your equipment has your Sense identified? I was shocked that it found my 3 heaters so quickly that are powered through my apex. It still doesn't want to find my pumps and whatnot, but maybe that's because they tend to power cycle a lot due to the programming. I mostly bought sense to track my tesla energy costs for tax reasons but it's a nice bonus elsewhere.

 

[User1]

It would be difficult/costly to power just your tank along on solar. Now, if you are talking about installing a system for your home to offset the energy costs, yeah, depending on your geography and local incentives.

My ultimate goal is to do home solar with some battery backups (probably Tesla powerwalls). Then I'd be saving money on power and giving myself power outage security without dealing with a generator. I'll need a new roof in 5 years so I'm hoping the Tesla solar roof tiles are fully rolled out by then (and hopefully a little cheaper).

How much of your equipment has your Sense identified? I was shocked that it found my 3 heaters so quickly that are powered through my apex. It still doesn't want to find my pumps and whatnot, but maybe that's because they tend to power cycle a lot due to the programming. I mostly bought sense to track my tesla energy costs for tax reasons but it's a nice bonus elsewhere.

I'll have to check because I do not believe it has picked up anything on the tank. I'm also going through an Apex so will be interesting. I have 1 heater, a pair of Cor 15's, and small DIY LED drivers. So maybe the heater?

It picks up some things quickly like a pair of 52 bottle wine cellars I brought online two weeks ago but other things not so much. I picked it up to see Solar power generation output. Since we purchased our unit outright it isn't required to have any sort of monitor or productivity information. I was a bit frustrated and gave up arguing with the builder and have since found Sense to at least track. This way if something is off I can at least visually see it. Good little product with some interesting potential.

I'll get back to you on what it found tank wise via PM - have a good day!

 

[DLHDesign]

A big piece of my previous and current builds has been figuring out how to run them in the case of a power loss. The best solution for me has been the simplest - a whole-house battery (specifically; a Tesla Powerwall or two). This relates because the Powerwall (as with most batteries) really benefits from an existing solar system that generates excess power during the day. In the previous house, I was able to install a system that was able to power the house and charge the battery to full during the day, then we could draw from the battery for about 80% of the night before the battery reached it's limit (I had it hold 20% for emergency coverage at all times).

By the math I ran several times, the solar and battery would have taken ~10yrs to pay off (it was a self-installed solar system). We sold the house before we could realize that, but took the battery with us. I doubt that the costs could have justified the energy offset entirely, though it did help to keep us out of the upper tiers (read: expensive levels) in our energy bill. So while it likely didn't save us money per-se, it did even out our electric bill and make each month more predictable. Once the battery was installed, the balance tipped in favor of having the system. But with the battery, the main gain was in the emergency fallback more than the direct cost savings. It came into play several times - saving the tank from an extended outage at least twice, and shorter-term outages that likely wouldn't have impacted things many more than that.

I'm still waiting for the battery to be installed at the new house (silly permits taking forever...). Once it's in, I'll add another so we can get through the night and then likely size up my solar system to ensure I can charge them both during the day.

 

[DLHDesign]

It picks up some things quickly like a pair of 52 bottle wine cellars I brought online two weeks ago but other things not so much.

I worked for a company that was doing something similar with water flow during the early-stages. Turns out that determining one device from another is quite difficult. Even with complex algorithms in place, we had to manually train the device on almost every specific use case. Every faucet nozzle we tested resulted in a statistically significant different flow. Even changing the pipe layout (as we all here know from our return line plumbing) resulted in readings that were different enough to require recalibration. What we ended up working on were algorithms that could create algorithms. Very complex stuff that seemed to involve more chaos theory than normal logic... In the end, the device was the easy part - the software the hard part. Rather like how speech recognition had to grow and develop, water (and I'm sure electricity) also "speaks" it's own language. And with each device having it's own dialect, creating a Babelfish becomes a rather difficult chore...
I've been thinking about the Sense myself. But I'm not sure how long it will be before they have enough identified data patterns to make it anything more than a gross relative meter. And since the Powerwall provides that functionality already, I don't figure I'll need one.

 

[basement reefer]

I have considered it and my tank is small enough to do it reasonably.

It would also be an option to make a larger tank more feasible. I would go with a larger tank too if possible.

Maybe there are some other types of systems that can be used, like those vacuum pipes used to heat up a big body of water may stay warm enough throughout the night.