Working with the Sun

Comet Solar installs solar systems on several islands in the Caribbean. Because of restraints by utility companies and island governments we decided to try an experiment in off-grid solar. We are using our home in Anguilla as the test case since we are committed to the use of solar as a new way to power homes and businesses in the Caribbean. This blog is about our experiences and the pros and cons of going off the grid.

We are leaving the first article about the technical side of off-grid solar at the top of the blog.

The equipment - the technical stuff

The equipment - the technical stuff

The Set-up In order to move a modern home off the grid, the system has to be able to support the power requirements without too much ch...

Wednesday 13 April 2016

Generator or Off Grid Solar?


Hurricane season approaches and Anguilla gets hurricanes. It is a fact of life and because our electric lines are above ground, we often lose power, maybe for days or weeks or even months at a time (remember Hurricane Luis?). This can be a bad situation for people who live and work here and don't have a way to generate their own power.
What can be done?

Fossil Fuel Generators

First thing people always think about and figure out a way to buy is a fossil fuel generator. They come in all sizes and there are several ways to fuel them.

Propane Generator

 Generac Generators
If you have a big house and you live in an urban setting, having a propane generator is really the way to go. They are quiet and can run for a long period of time.  Price for a 7kW propane generator is about $3,000.00 US
Propane is available on the island.
It must be delivered. Make sure you stock up before the storm.

Diesel Generator

The next best option is diesel. Not nearly as quiet and it is messy. You must fill the tank. You must buy and haul the diesel and you must change the oil and if you don't service your generator it will soon fail.
Diesel generators also come in various sizes. If you get a small one and expect it to run your entire house, it will fail. That's a lot of money to spend for disappointment. You must understand what you need, how much you can afford to spend and then sort out your power load to accommodate the generator.
The 6 KVA Launtop in the photo cost $1495. US.
It might run a small house but not a large house and in short 3 hour run times.

Gasoline Generator

The last and worst option is the gasoline generator. They are not efficient, they are expensive to run and they are dangerous. Dealing with gasoline at the station where you must purchase it and at home where you must pour it into your generator is messy and dangerous. There are rules to follow for safety but people tend to ignore them when they are in an emergency situation such as a power outage after a storm. They also require oil and maintenance.
A 5 KWH generator holds 5.5 imperial gallons. The generator  will run for 9 hours  but it is not recommended as it will reduce the life of your generator.
We do not sell gasoline generators. They are noisy, messy, dangerous and inefficient.

Generators are used for emergency situations and not much else. It sits in your garage or back room or under a tarp until that moment when you must fuel it up and turn it on. Forgetting that much needed maintenance may lead to disappointment when you need your generator most.

One thing to remember when using a fossil fuel generator is that at some point you have to turn it off. People generally do this at night and that is OK except that much  needed fan can not run because you have no power. Having power if only to run a fan at night is important after a hurricane. The air is still and hot and you need to sleep.




Solar Generated Power

Off-grid solar system
The smart option for Anguilla is a solar generated system. 2 KW system $5,000.US
This is fairly new to the market. An off-grid solar system. They too come in many sizes and they require batteries. Unlike any of the power generators mentioned above, solar power generation requires very little maintenance and no re-fueling. They are basically a self contained unit that creates and stores power all day long as long as the sun shines.
So…you install your solar panels. Or, if you don't want to keep your system running all the time you place your solar panels in a clear to the sun area facing south, hook it up and let the batteries charge. Depending on the size of the system you can choose to either hook your system into your electrical panel or run extension leads to the items you wish to run such as a refrigerator and lights. The system will run your items all day long using the sun as power and at night the batteries which have been charging all day will continue to keep the power coming. All you do is make sure the system is running, keep your batteries topped up with battery water (once a month) and let the sun do all the work. The inverter that comes with the system turns the suns energy into electric power. There is no re-fueling or changing the oil. There is no maintenance except tending to the batteries. If you keep your system safe and dry it will just keep running. The solar panels are made to be outside in the sun free of obstructions such as trees or buildings that block the sun. That is about it for a solar powered generating system.

How do you get emergency power?

Diesel
Gasoline


Cost of Power Generation

Diesel and gasoline generators require fuel and oil. On Anguilla we use the imperial gallon.
1 gal. US = 1.2009 Imperial gal.
Diesel Fuel
In Anguilla we pay $13.21 EC per gallon for diesel fuel. It will cost approximately $92.47 EC for 7 hours of run time on your diesel generator.
Gasoline
We pay a little less than $14 EC for an imperial gallon of gasoline.
A 5 KWH gasoline generator holds 5.5 imperial gallons. It will cost $126.00 EC for 9 hours run time.
Propane
100 gal, container
A propane generator requires at least one 100 gal. tank for proper operation. At $16.00 EC per gallon that is $1600.00 EC to fill the tank. 10 hours run time will require 7.3 gallons. About $81.00 EC a day.

Solar
The cost of solar generation is free. After your purchase the solar system the sun charges your batteries and it doesn't charge you for charging your system. The only time you lose power is when the batteries run out and if you plan careful and pay attention you should always have power especially for important things like your fridge and a fan.

The math is simple...if we have an outage for 5 days the cost to run your house on a propane generator is $405.00 for 10 hours a day. The cost for a diesel is $462.35 for 7 hours a day. The cost for a gasoline generator is $630.00 for 9 hours a day. The sun is free.
Prices of fossil fuels is subject to change. The sun is not, let's hope it doesn't get a union.

Things to consider when using fossil fuel generators:

Do not let your generator run out of fuel.
You must wait until the generator is cool before refueling.
It is not recommended to run a generator all day and all night. It is recommended to run it for 3 hours at a time, then rest and refill.
Do not run your generator in an enclosed area, it is dangerous and could be deadly.
When you turn off your generator you lose all power to your home.
A generator may take 2 quarts of oil or more so keep it handy.  Don't forget you also need oil filter and an air filter.

Propane generators require propane fuel. It is highly recommended that you have at least one 100 gallon tank for proper operation of your generator. This tank can not be refilled by taking it to the propane dealer, the dealer comes to your house to refill this tank. These generators also require a yearly service by a qualified propane generator technician.
Running a generator that requires fossil fuel will run your house in an emergency. But it is costly and continues to cost for the entire time you are using it. If you do not maintain your generator it will fail. Maintaining a generator involves service and starting even when not in use. If you do not do this your generator will fail when you need it most.


Solar Generated Power

Let's say you decide to try creating your emergency power using solar. A storm is coming so you pull out your solar panels and set them up. At this time it is not necessary to connect your inverter to your appliances or your transfer switch. You are simply topping up your batteries.
Solar panel on roof.
The storm arrives and your regular power goes down. You have now connected your inverter and stored your batteries in a safe place.  You have power because your batteries are charged. When the storm is over you place your solar panels in the sun and recharge your batteries. Since your appliances are already connected they will continue to run. They will run all day because the sun is shining and at the same time your batteries are charging so you have power for night time use. And just because the sky may be overcast does not mean your solar system will not keep charging. It may be at a reduced rate but you have all day. Keep an eye on your inverter for information on the state of charge of your batteries. That is all there is to it.
You do not have to refuel the system.
You do not have to change oil or filters.
It requires no maintenance except keeping the batteries topped up with battery water.
When you are done using your solar system you can pack it away until the next storm but why would you? Why not leave it running to power important items in your house? You will be saving money and using your system so it can pay you back for the money you spent.
It sounds pretty simple. The Caribbean has a great resource we are not using. The sun can help us so much in getting away from the use of fossil fuels, protecting our environment and saving us money.


Other Solar Storm Solutions

Another solution in dealing with a no power situation in a storm is a smaller version of an off-grid system. This will get your through the storm with the ability to charge your phone and have some lights. They are a great way to have a little comfort in a difficult situation.

Keep a few emergency lights on hand so you can carry them around the dark house. They have their own solar panel built in and give off enough light to use on the kitchen table for dinner. Great for the kids so they have a bedside light. 
They beat candles as there is no danger of fire.

Anguilla has more sun than anything else. It creates an environment that people love during the winter months and during the summer can make this place almost impossible to live in but what about if we think about it in a different way? What about if we use the sun to produce our energy needs. It will save us money. It will stop the use of fossil fuels that pollute our island. It will make our island more popular for people that consider the benefits of solar energy as opposed to fossil fuels.
Solar power can make Anguilla a powerful place.

1 comment:

  1. Yes they do Emilia but we are trying to point out that a solar battery system will do the same thing but not use fossil fuels. They will also supply the home with power at night which you can not do with a gasoline generator unless you are prepared to get out of bed all night to fill it. Gasoline is the worst solution to supplemental power because gasoline is very dangerous to handle. If you are going with a fossil fuel generator choose a diesel or propane model instead, diesel is not nearly as dangerous or flammable but still must be refilled unless it is supplied by a large tank such as your example of a hospital. They are also usually very noisy.

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