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Battery upgrades? Yes we do!

Not all batteries are made the same. Some are designed for maximum current (car batteries). Some are designed for long life. And some are designed to cycle. And they can be even made designed with a couple of these ideas in mind.

Lead Acid batteries are not dead. In the right application, they are far more cost effective than any lithium battery. What application? Long life back up power. If you cycle the batteries less than 100 times per year, a good quality VRLA (Valve Regulated Lead Acid) AGM (Absorbed Glass Mat) work great.

Lithium Ferro Phosphate batteries.If you are going to LIVE off-grid, or you are traveling a lot (RV & Trailer), a LiFePo4 (Lithium Iron Phosphate) is a much better battery and even at today’s prices, will be more cost effective.

But back on VRLA AGM, just before Hurricanes Marco and Imelda entered the Gulf of Mexico, one of out clients contacted us to upgrade their batteries. The UB-4D is not a great battery for standby storage. The posts are made of lead. The always seem to leak and they have high resistance in heavy draw.

Absorb Glass Mat (AGM) batteriesThe C&D TEL12-210F is an excellent upgrade. Side by side, the UB-4D has a capacity of 200AH, while the TEL12 has a capacity of 230 AH. This is a 15% increase!

My customer had a nominal 19.2 kWh of storage. But increasing the batteries from 8 to 12, and upgrading to the TEL12, they now have 33 kWh of storage. 33 kWh will run their 4 ton air conditioner about 15 hours. They have 17 kW of solar, so they produce about 100 kWh during the day. They should have enough power to run everything when the power fails, day or night.

The best battery is the one that does what you need it to do, for the lowest price.

Coronavirus

Novel Coronavirus / Covid-19 & Panic

Coronavirus

Coronavirus

There are a lot of concerns about this new virus. And many are valid. It is “new”. It spreads fairly easily. Humanity does not have an immunity to it. And at the moment (3/10/2020) there is no vaccine. Scary stuff.

The good news comes from South Korea. They are doing extensive testing of the population, finding everyone who has the virus. If this is correct or close to correct, the mortality rates drops significantly. Worse than the average flu, about the same as recent “bad flu”, but nothing like the medieval “Black Death” in any of its forms.

With extensive testing, South Korea seems to be finding all of the cases. If the data is correct, the fatality rate is ~0.69%. The Flu in the US, by comparison, last year had a fatality rate of only around 0.1%. So, yes, Coronavirus is worse than the flu. The 10 year average for flu is around ~0.2%. Which means some years are worse and some are better.

https://www.cdc.gov/flu/about/burden/2018-2019.html

I tried to find a WHO report on Korea, but the latest Korea specific report is a month old. These three up to date articles match on the basic data.

https://www.worldometers.info/coronavirus/country/south-korea/

https://www.businessinsider.com/south-korea-coronavirus-testing-death-rate-2020-3

https://www.statista.com/statistics/1095848/south-korea-confirmed-and-suspected-coronavirus-cases/

Don’t panic. Don’t willy nilly buy lots of items, especially things you do not use on a regular basis. If you need hand sanitizer, buy only what you need so others can buy some.

Wash your hands! I think most people in the USA have been very lax about basic hygiene. This needs to change. Wash your hands often, especially after risky behavior (Hand shaking, visiting the toilet, touching your face, touching stair rails, door knobs, etc.). https://www.who.int/gpsc/5may/Hand_Hygiene_Why_How_and_When_Brochure.pdf

We need to reduce “nice” but risky behaviors. Hand shaking, cheek kissing, casual hugging, etc. Wave hello instead. Many of my friends are Spanish and French and they are having a hard time not cheek kissing. We need to make sure we “cover our cough”. We need to stop touching our faces, eyes, mouths. And when we absently do these things, we need to wash out hands. Again!

Listen objectively to verified news. If someone is passing around “information” on social media, and it doesn’t link back to a source, the information may be suspect. Don’t forward or share it. And when it does link to a source, verify that it is a source you trust. You can even use a search engine to verify, before you forward. This is a serious time, but we should not make it worse with potential misinformation or exaggerations.

I’ll update this page as more information in known.

Infographic on grid-tied vs. off-grid solar power.

How Mi-Grid’s Comprehensive Solution is Better Than Grid-Tied Solar

Congratulations, you installed a solar array at your home and the system is tied to the utility grid. If the solar doesn’t generate enough electricity, you can rely on the utility and you might even net meter power back to the provider. Sounds great, but what happens when the utility loses power?

You are out of luck. Utility distribution is susceptible year-round to storm outages, whether from snowstorms, thunderstorms or hurricanes because of the extensive network of strung wires. Ice weighs them down and downed trees yank them loose. Your solar array may be standing, but UL 1741 requires your grid-tied inverter to shut-down for safety’s sake. This prevents any power from a home from reaching the grid when repair workers are on the lines.

Here’s the beauty of a Mi-Grid energy management system: while disconnected from the grid, it operates on a stand-alone basis. Solar power can keep the lights on and that energy can also be stored to batteries within the configuration. If the batteries run low, a generator automatically kicks in to power the home and recharge the batteries, shutting down once the batteries are recharged.

Making Renewable Power Reliable

This is why the Mi-Grid can be installed as a grid-tied system or an off-grid system. It technically doesn’t need to be grid-tied. Hence, the smaller Mi-Grid sizes are ideal for remote locations as well as mobile applications, such as food trucks and RVs.

The brains of the operation can be installed in a variety of packages, including wall-mounted, indoor, outdoor or trailer mounted. The outside options are housed in NEMA 4 enclosures for durability. Mi-Grid systems range in size from 1 kW to 2 MW and can serve residences as well as businesses that want complete electric reliability.

When a Mi-Grid is connected to a distribution grid, that utility power enters the mix. The Mi-Grid is essentially a dispatch system that selects the lowest-cost available power at a given time. When grid-tied, the utility supplies power at night and can take excess power from the solar system during the day.

The batteries are kept full for backup and the generator sits in stand-by mode. This cycle runs daily, with solar power providing electricity during the day and the utility providing any needed power overnight. Mi-Grid ties together all of the energy sources, providing multi-layered power and backup.

As the consumer, you won’t see lights flickering because the shifts among power sources are seamless. For example, a customer of ours who lives in a rural area was surprised to hear at a community breakfast that everyone else lost power the day before when the local supplier dropped offline. He did not realize his inverter had kicked in under the Mi-Grid system.

Think of times when you have lost power and were out of commission when it comes to connectivity and conveniences. But it’s not just major storms that can cut into productivity and quality of life. Local power outages are fairly common events. Also, if you wish to live off-grid but not entirely replicate a previous century’s lifestyle, then Mi-Grid gives you that personal freedom. And at a lower cost than either a stand-alone solar system or a generator alone.

The other benefit to Mi-Grid is you don’t need to manually mess around with the typical emergency generator that requires frequent refilling of the fuel tank as well as oil changes. Each time you tend to such a generator, the power is turned off. Instead, the Mi-Grid generator is only turned on when the system’s batteries are low. By cycling the generator only when needed, the system saves on fuel and maintenance. And you don’t have the constant roar of many generators.

Why invest in solar alone when you can invest in a fully-integrated system to provide truly reliable power? Mi-Grid has you covered, grid-tied or off-grid, sunshine or clouds, day or night, 365 days a year.

 

What is Net-Metering?

Net Metering is a method of billing used by some utilities. Solar Production in excess of your immediate needs is exported to the utility. The utility measures the outflow and credits them against your inflows of electricity. You pay only on the “net” inflow.

For most Grid-Tied Solar PV, the solar energy is converted and fed into the existing AC electric system. This is done without regard to how much power is needed at any given time. The excess flows “Out” into the electric lines. The energy is available to be used by others.

Net metering is a simplified method of compensation for these out flows. Your electric bill is calculated at the “net” difference between what you consume and what you produce. You use 2000 kWh per month. The solar array produces 1500 kWh. You pay for 500 kWh. Simple, huh?

Except, the price you pay your utility really comes from two different pieces: Energy and transportation. In electric bills in most of Texas, you see both retail electric energy charge and the energy transportation charge. Remember, there are costs in maintaining the electric lines, PLUS the cost of maintaining the power plants you use when the sun isn’t shining.

When I “make my own” energy, I am reducing the energy I buy from the utility. When the sun isn’t shining, or not enough, I buy power from the utility. But if I make too much, I have to do something with it. I sell it to the utility. But this energy I sell has to be transported to other users. The utility transports the power.

Most grid tied users see the utility as a “storage” system. They “store” power and then use it later. But it isn’t really stored. When power is pushed onto the grid, a power plant somewhere has to reduce output to compensate. But the power plant can’t shut-down because it has to be available to provide power in case more power is needed. For example, when a cloud goes by.

When solar makes up a tiny percentage of the network, it doesn’t affect the overall economics of the power system. It may in the end be cheaper for the utility to bill “net meter”. But as the percentage of installed solar goes up, the “loss” by the utility goes up with it. It must compensate by raising the price of electricity. Your neighbors without solar pay.

It really is fair to compensate a solar producer only for the electric generation portion of the power.  As renewables become more wide-spread, net metering will be reduced and eventually abandoned. Hawaii, California and Germany are abandoning net metering. Massachusetts, like many states, reached the limit of net metering.

Mi-Grid stores your excess renewable energy for your own use later. You truly are “NET” with the meter, since you do not sell power to the utility, you save it for yourself to use when you need it.