[KaiserJeep]

I don't think the word "advocate" means what you think it means. You probably meant to say "apostle".

We just did the annual true-up statement from PG&E. They paid us $530.80 for our surplus electricity this past year, which didn't quite cover what I paid them for natural gas. But it's just GREAT living in a "net metering" state.

BTW, have you seen any impacts to the solar biz from Trump's tariffs?

[Outcast_Searcher]

BTW, have you seen any impacts to the solar biz from Trump's tariffs?

Since the news on Trump's tariffs seems to change pretty much daily, how anyone can have much of a clue of where we're likely to end up in a month or a year is beyond me.

And almost all the news implies or states meaningful financial harm to almost all the voters.

I'm no political strategist, but angering almost everyone somehow doesn't seem QUITE like a good political strategy to me.

Is there some reason I'm missing that the GOP part of the Beltway doesn't wake up and make Trump an offer he can't refuse re Tariffs?

[Cog]

The purpose of tarriffs is leverage more equitable trading deals. Business 101. Unless you believe the usa should get screwed on global trade deals like we have been for the last 30 years.

Saying pretty please has not worked to get foreign countries to stop having tarriffs on usa produced good.

[Ibon]

The water that runs from our taps is untreated and pure, gravity fed from a cistern that is fed from a pure spring. Our 8kw of 24/7 power bakes our bread and brews our coffee. We run 5 buildings. The only utilities we pay for is internet at $ 58 a month and propane gas which is around $2500 per year.... but we don't pay for this ..... the tourists do!!

[KaiserJeep]

In 10-20 years you won't be able to afford propane, any more than I will be able to afford the heating oil on Nantucket. So make a plan for solar or wood cooking and water heating. In an eco-resort, you could even make good advertizing from such, and use it to justify a price bump...

[Outcast_Searcher]

The purpose of tarriffs is leverage more equitable trading deals. Business 101. Unless you believe the usa should get screwed on global trade deals like we have been for the last 30 years.

Saying pretty please has not worked to get foreign countries to stop having tarriffs on usa produced good.

Thank you for stating the blatantly obvious.

And the tit for tat games being played, messing up prices for almost all voters and for MANY Trump constituents is good strategy? I'd say NO.

...

Now, I'm sympathetic to some of the concerns Trump has, especially the issue of China stealing US intellectual property. I just think there are better and more nuanced ways of negotiating then Trump's favored style of barging around like a bull in a China shop (no pun intended), and doing little or no net good.

The Chinese like to save face. Quiet, measured, behind the scenes suggestions via trade reps, letting the Chinese know that working with us on that issue would be very much in their interest, for example, might be a lot more productive.

Actual tariff wars should be the LAST thing to try, and Trump's idea that he can definitely "win" such a battle is ludicrous on it's face -- assuming pissing off almost every voter isn't on his agenda.

[Ibon]

In 10-20 years you won't be able to afford propane, any more than I will be able to afford the heating oil on Nantucket. So make a plan for solar or wood cooking and water heating. In an eco-resort, you could even make good advertizing from such, and use it to justify a price bump...

We already have more than enough "sustainable advertising". I also have already purchased all the parts for solar water heating even the Danfoss small pumps that run on 35W of power and are rated up to 180 degrees for circulatiion. When you have 4 cabins and sometimes dozens of guests it is very very hard to meet the demands of everyones early morning showers etc with active solar water heating. At this point propane is cheap enough I don't worry but I am ready if prices soar.

Just taking 30 meters of 3/4 black polypropalene tubing and filling it with water and letting it sit in the sun for 20 minutes produces burning hot water. Circulate that in an insulated tank and presto. at 1900m the sun is intense. Sometimes I am lazy though, there is just so much one can do at a time...

There is also a natural thermal hot spring 1.5km from our cabins and guests hike down and soak. So we also have geothermal hot water source int he area. A geologist said the underwater hot aquifer is probably under our land if we would drill for it... I just don't want to mess up the hydraulics and screw up the public hot spring near by or I will piss off the locals!

[Tanada]

Ibon it seems with your abundance of hydroelectricity that an on demand electric water heater might be just what the doctor ordered. The new ones are very efficient and capable of producing copius water without need of a large insulated storage tank. If you ever get around to building the solar rig a simple T fitting with valves will let the solar heated water flow through the on demand system reducing its draw to nothing when the sun is out heating the array, but still providing all you need on cloudy days or at dawn after the longest night of the year when the array has cooled to air temperature. even then the air temperature water as feed to the system strongly reduces demand because the 65 degree water needs much less heating than 50 degree spring water in terms of energy input.

We are planning to install an on demand system someday, but do not see the point in pulling out the still functional high efficiency tank the previous owners installed until something breaks down on it. The new system is only about $50 more than a replacement tank system and the efficiency is much greater because it doesn't keep a tank of water heated when not in use.

Something like this one is more than enough for any normal bathroom use for showering or filling a bath tub in a reasonable time interval, https://www.homedepot.com/p/Stiebel-Elt ... /203210876

[Ibon]

Ibon it seems with your abundance of hydroelectricity that an on demand electric water heater might be just what the doctor ordered. The new ones are very efficient and capable of producing copius water without need of a large insulated storage tank. If you ever get around to building the solar rig a simple T fitting with valves will let the solar heated water flow through the on demand system reducing its draw to nothing when the sun is out heating the array, but still providing all you need on cloudy days or at dawn after the longest night of the year when the array has cooled to air temperature. even then the air temperature water as feed to the system strongly reduces demand because the 65 degree water needs much less heating than 50 degree spring water in terms of energy input.

Thanks for that. I have a 75 gallon electric water tank that in the 1st years here before we had all the buildings up we used this by swtiching out the 4500W heating elements for 2500W. It just took a little longer to heat up the water but worked. Now I have that 75 gallon unit idle just waiting to tie this in to solar water heating once I get around to working on this.

Your on demand suggestion is good but I will explain to everyone interested the big challenge we have here with power distribution and usage. Our pelton wheen is connected to a 220V AC generator which delivers the constant 8KW. There is no inverters or batteries. It is a simple design where a load controller distributes power between usage and a dump which is just a cistern with heating elements that burns off unused power. The dump has 8 channels so I already have channels 1 and 2 heating up a separate electric hot water tank. When it reaches max temperature the thermostat shuts it off and channels 3-8 dump unused power which isn't much.

The challenge here is just like any other grid, managing peak usage. We have a lodge and 4 cabins and the generator and pelton wheel is right about in the center and power runs in all directions to all the cabins. 8kw sounds like a lot but there is transmission loss. If you add all the underground power lines from the generator to all the cabins we are talking about over 2 kilometers of transmission. 5 refrigerators and two floor freezers and LED lighting throughout the project is the base load.

So here is a typical issue. My wife Alma is preparing breakfast on a busy morning. We have 15 guests. In the kitchen we have a toaster, coffee machine, electric pot to boil water, microwave. The gas stove has an oven that starts the gas with an electric heating element that glows. IF we do not have full power the oven wont gas on.

Tanada's suggestion of an electric on demand water heater would work if it was just a single household. But imagine you have 3 or 4 of these running in different cabins just when we are using all the above appliances in the kitchen preparing breakfast not to mention some hair dryer that a guest brought up in their suitcase. The oven wont turn on the breakfast muffins dont get baked, my wife is freaking out and I am running around trying to shut off appliances. This scenario has happened.

Peak load requirement is always the issue. 8KW is a lot of power 24/7 but there are moments we need more than 8KW. Our system has no inverters and no power storage. That is weakness at the moment. Hydro is wonderful to produce direct AC and abundant power but to store that power we would need to convert to DC, have a battery pack and then inverter back to AC again. It is pricey and cumbersome. I love how simple our current system works.

The other advantage of using propane to heat water and cook is the redundency. If we have a service issue with the hydro unit we can still cook and heat water and we can still provide guests with a minimal of service while we get the system back on. We are too remote and there is no Home Depot 5 minutes down the road.

Currently each of our cabins has LED lighting and a refrigerator and a modem and WIFI. We do not put in any other electrical appliances in order to reserve all power to the kitchen area of the restaurant. That is how we manage.

I am interested to research batter stroage and the inverters from AC - DC back to AC and price this all out but I have not gotten around to it.

Anyway, that is our situation briefly. Any ideas would be appreciated, I am always looking for ways to optimize.

Thanks

[KaiserJeep]

Not sure I agree with baha, even though we are both EE's. IF you could build a largish superinsulated storage tank for heated water I think storing energy in the form of preheated hot water is the way to go. Thermal solar with PV-powered active circulation is a lot more efficient than PV and heat pump when it comes to making hot water, even though he is correct - the heat pump makes more BTUs with less electricity than resistance heating. Then you could distribute such hot water to the points of use through insulated hot water piping. A continuous insulated loop of hot water that goes through each bathroom and kitchen would eliminate the need for point-of-use water heaters as well, and eliminate water running until it reaches full temperature.

Nothing about the above would prevent you from using your current resistive water heaters as power dumps either, or as water heaters at night when the PV is offline. The heat would be retained in that same water tank, not dumped is all. It is hard to be too specific about the design elements without knowing the average consumption either. The good news is that the DIY solar heating info and modeling software found online could be easily adapted to figure it all out.

I do not know if daytime A/C is needed, but I should point out that a heat pump water heater "dumps" cool air, which could be used for conditioning living space or food refrigeration.

Total system design would be complex, and you would want redundancies in the system, no single points of failure. As long as gasoline or diesel or propane is cheap, that would be the first choice for backup power. Your system design would be for something that only uses the FF's for backup electricity if you have some sort of equipment failure.

FYI, electric induction cooking uses half as much energy as either propane or conventional electric stoves, with zero emissions. The main limitation is that all of your cookware must be cast iron or steel, or laminated like the All-Clad cookware, induction-compatible.

I do agree with Baha in that you need to study the requirements for hot water demand during several typical weeks before detailed system design.

[Ibon]

Thanks KJ and Baha.. Much appreciated. When I was working in Thailand we put active solar thermal units on the roofs of the villas and we did have many maintenance issues and eventually abandoned using them. Pressure regulators failing and pipes bursting and being a couple meters above high tide with salt spray didn't help. Up here in the mountains I am considering it though.

The heat pump water heater Baha suggests is actually perfect here considering that 300w would be minimal power draw. The problem is they do not sell these here in Panama and marine freight and duty would make them quite costly but I would still do it as it will pay for itself in not too much time. What about buying the components and retrofitting my 75 gallon electric hot water tank? Baha, what do you think?

Long term I am considering a hybrid solution, in the low season when we have few guests or its just the two of us we could use the heat pump or thermal solar and when we are in the high season I don't mind the convenience of propane to satisfy 15 peoples hot showers since having 15 people here means we are bringing in good income so no problem burning propane then. There is big seasonal variation in our guest count so it would make sense to go with efficiency in the low season and just suck on that propane in the high season. At least while the price of propane is within reason.

[Tanada]

Several years back I saw a demo of an electric water heater that used microwave bulbs in place of resistive heaters to increase the tank temperature. The claim was a 2500 watt microwave system worked much faster and more efficiently that a simple electric heating element of the same wattage.

[EdwinSm]

I am not sure that I am a "Solar Advocate". Our panels have been in only for a week, and I need to get the first bills to see exactly how the electricity companies handle the two way traffic of a grid tied system. [To go for a battery system that Baha loves, we would have also needed to put in a wind mill given our geographical situation, and the budget did not stretch that far.]

I am torn between two polls of thought 1) this is a great insurance against raising costs, helps a tiny amount with CO2 reduction (supposed to generate almost 30% of our annual consumption), helps a tiny amount with energy independance.... 2) the doomer in me made me panic and throw away a large amount of money which could be sitting in the bank earning 0% interest.

What I am an Advocate for in this latitude (60.162672) is ground heat exchange pumps. They are costly to install but ours paid for itself (in savings of heating oil against an increase in electricity use) in 8 years. The pay back time would be less if I included in the calculation that that old furnace was over 30 years old and needed replacement anyway. The pumps also reduce the need for so much energy input:- so the same warmth in the house for about 1/3rd of the bought energy input is a great step on the transition to lower energy use.

[Outcast_Searcher]

I am torn between two polls of thought 1) this is a great insurance against raising costs, helps a tiny amount with CO2 reduction (supposed to generate almost 30% of our annual consumption), helps a tiny amount with energy independance.... 2) the doomer in me made me panic and throw away a large amount of money which could be sitting in the bank earning 0% interest.

To me, the strongest case with solar plus batteries is the relative energy independence (especially for emergencies) without needing an expensive and maintenance-requiring generator setup.

For the financials, I'm far less convinced, thus far. You still have the utilities fighting hard to screw solar customers re the financials, breaking contracts, not paying much for net metering power from the customer, etc. So if you have a "good deal" on that now, that could change for the worse. To me, when governments allow contracts to be broken, I refuse to trust them any more. So Nevada apparently changed what they're doing again for the better. What's next?

https://www.npr.org/sections/thetwo-way ... incentives

Unless your electric bill is nasty (and conservation might be a cost effective way to help), falling prices for equipment and improving tech might be better economics for the next several years than taking the plunge.

I'd like to see how Tesla Powerwall battery (and competitor) prices evolve, for example. I ALSO want to see more about the fire risk of such systems BEFORE putting them in my house, thank you very much.

...

As for 0% interest, there's a better way. "High Yield" savings accounts in major US online banks are now yielding in the area of 1.75% interest and rising with overall interest rates.


The main constraint is only 6 withdrawals a month (like a typical money market account), so you can't use them for the household checking account, for example. FDIC insured to a $quarter million.

Or, 1 year CD's paying more like 2.4%.

Nothing earth shattering, but helps keep up with inflation for the most part.

Disclosure: I have no direct investment in any financial companies. I only mention these as a happy savings account customer for most of the past decade with Ally Bank and American Express Bank via their convenient relatively high yield online money market accounts with minimal balance requirements, muss or fuss, and acceptable customer service. The main constraint is only 6 withdrawals a month (like a typical money market account), so you can't use them for the household checking account, for example.

The nieces and nephews have been happy with them.

[KaiserJeep]

I believe that the ideal location for the whole house battery is the wall shared between the attached garage and the house. That is a space that is already fire resistent with thicker drywall and a lower concrete floor and a fire-rated door to the home itself. It is not heated space typically, but does often contain furnace and water heater and laundry equipment, meaning that it won't see extremes of cold.

I totally agree about battery management, by the way. Which is why laptop and tablet and other lithium batteries for electronic devices use multi-conductor plugs, to allow seperate monitoring of each cell in the battery, and battery temperatures as well. That laptop charging software was scaled up and refined by Tesla, for cars, residences, and even utility-scale batteries.