How to survive with a small inverter

Good Inverters are expensive, especially the bigger they get. Even worse, many seemingly “good deals” that you find in some stores will break quickly, due to low quality. Question is do you really need a 2000W inverter to run a anti-brown out backup system? In a typcial house most modern appliances run usually at very low wattages, like LED lights (3-9 Watts), LED TV (30-120 Watts), Internet router (5-10W), Laptop (20-60W), Tablet (5W), so for those you wouldn’t really need a strong inverter. Plus strong inverters usually prefer to run at higher loads to have a higher efficiency – which can be 90% opposed to 20%! Other cheap inverters, while bragging with 2000W on the casing, mention quietly in the depths of their manual, that they survive those 2000w only for a matter of minutes or even seconds (!!).

Now the only important appliance missing in that list is the refrigerator, which happens to be a little more hungry. Not so bad though, between 90-180W usually. This important device proves to be the main challenge in a off-grid solar setup, as it requires a pure sine inverter which are significantly more expensive and durable than those 2000W deals from the electronics discounter around the corner.

The problem is that a tall fridge that is rated at for example 150W needs a start-up surge of around 1500W just for a blink of a second, but too much for a 500W pure sine inverter to provide. Solution here is to look for an inverter fridge, that don’t do this on-off thermostat game that regular fridges are doing, but they do run continuously at a lower wattage. No 150W then 0W then 150W then 0W … , but permanently at 45W for example, which is much easier on a solar system. Just as an advise if you are still in the market for a new fridge.

If you have an inverter fridge and you want to try if it runs on a 500W inverter you are welcome to try before you buy.

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The best direction your panels should be facing…

Traditionally and internationally most solar panels in the Northern hemisphere are facing south, to harvest the largest amount of solar energy. However as we are located in the Philippines a south-east direction might be considerable, as our tropical skies have a tendency to be cloudy in the afternoon, while the mornings tend to be sunny.

A traditional setup is good, when you have a large battery bank that needs to get as much as energy as possible, or if you are grid-tied and you want to deliver the highest amount of kWh possible.

Recently, especially in areas with lots of solar systems there is a new trend to install east and west facing solar systems, to provide energy at times when it’s most needed (eg. when going and returning from work/school). Plus in countries like Germany with huge solar installations, there is a nationwide oversupply of solar energy during noon hours, which is countered by a setup like this. It harvests less energy, but the time it does produce energy is more valuable.

Price reduction

Our panels in single retail quantity are lowered to P58/Watt while maintaining the same Grade A quality and source. Discounts/freebies for volume buying available. Also the prices of our controllers have been significantly lowered.
Note also that the manufacturer of our panels offers 12 year 90%, 25 years 80% power output warranty.

How to mount solar panels on your roof.

Look for a south or east facing place on your roof. Make sure it will not be affected by any shadows. Even a small shadow on a corner of one of the panel will equally slow all of them down.
Solar panels don’t like to sit closely to the roof. Its recommended to keep 7 cm or more distance, so the panels can give off hot temperatures more easily.
image

We usually mount them on c-shaped aluminum beams that are conected with L-shaped aluminum bars. The beams can be fastened with the existing tec-screws to the roof, while for the L-bar short nuts and bolts can be used.
While the panels have mounting holes in their brackets underneath we find it easier to mount them from the top with long bolts that are holding the panels with oversized washers.
image

For the wires we use a flexible hose to give them additional protection from the elements.
As a nice side effect the panels will now shelter your roof from the hot sun just like a Nipa palm roof, so your house will stay cooler.

How to install a solar water heater

Despite their impressive size these devices are so easy to install, that you can just do it with the help of your regular Handyman. Typically our customers bring their Handyman along, when they pick up a unit.
We will then take the time to show and even practice the setup procedure.

Installation demo at our farm

As you can see in the picture the heater sits on a aluminum bracket. The bracket is initially designed for a flat roof, but you can cut the hind legs as needed, to adapt it to diagonal roofs. The minimum angle is 26 degrees.
For the roof installation, we usually just open a few of the existing tec-screws and use these to attach the bracket to the roof, no drilling needed – the roof stays as it is.

Then the tank is fastened to the bracket and the 15 glass tubes can be inserted. As a lubricant you should use water, or some diluted dishwashing soap. Once you are done installing the pipes, it is recommended to cover them with a canvas from the sun, until they will be filled with water.

The small autofeeding tank is installed with the nipple onto the top inlet of the tank. On the side of the autofeeder tank you connect the water line coming from the city.
Solar heater on a diagonal roof
The easiest way is to run it on the outside of your house and “T” into your existing water line, or you can hide it in the walls, which is a good option especially when you are still building your house.
The warm water outlet is in color red on the main tank, just connect a pipe here and run it into your bathroom. The most comfortable is to use a mixing armature, or the simple Pinoy way would be to mix the water in a bucket for tabo use.
For the hot water pipe you may want to consider PPR pipes (heat proof plastic) as GI might have a reduced life expectancy given the high temperatures. PPR can be found in the hardware stores of large cities – they might also borrow the needed welding tool that you need to connect the pipes. If your pipes are already in place, GI is ok, too – we are using GI ourselves.

CAUTION: Be careful not to twist any of the pipes at the solar heater tank. You have to hold them with a wise grip and prevent them from twisting, when you attach pipes to it.
The blue pipe is the cold water in
Once you are done, make sure the glass pipes are still covered by canvas (otherwise they would be extremely hot) and then allow the water to enter. The feeder tank will act like a float valve and close the water supply once the tank is full.
During strong sunshine you might see water dripping down from the feeder tank, this due to the expansion of the water and the boiling. A mild hint that you should use more hot water 🙂

Website content

The website Highland-Solar.com was born in April 2013. It might not be overflowing with content and details yet, so if you find something missing, even tutorials and such, don’t hesitate to ask and we will add it to the site ASAP and we will continue to do so, until all info is complete.
Prior to asking make sure to check the info on the product, FAQ and tutorial pages.