Alternative Power recommendations
Quite a few of our clients live totally of the grid, and we think that is pretty cool! The info here will be very helpful to anyone thinking about alternative energy. First thing to contemplate is – do you have sufficient sun or wind on your property? If you are building in Puna, wind is generally lacking for most. The beauty of wind is if you have some, you might be able to keep your battery arsenal at a healthy voltage at night without running a generator. Which brings up another important point- the easiest, cheapest, most efficient and greenest way to go as far as having alternative power is to be hooked up to the grid. Why you ask? Well, if you are being powered mostly by PV panels during the day, and you are off-grid, your battery arsenal will most likely be maxed out by 10 am, and all that power you are producing via those panels is being totally wasted because if you were to over charge that arsenal, you quickly destroy it. If you are on the grid, you spin your meter backwards, the grid holds that energy, and delivers it back to you whenever you need it, even at night, with no need to fire up that generator. Refrigeration makes it so you generally will need to run that generator all night, or turn off the reefer for some time every night as refrigeration pulls a massive amt of power. Think about that one for a while! Because of this, many buy propane powered reefers. They are pretty effective but small and much more expensive. They beat running a generator all night! And not having to run that generator at night means no carbon monoxide getting into your home either. Hot water and cooking round out the other two high energy consumers. Off or on grid folks can use either solar hot water or on-demand propane hot water, both work well if designed well. Gas for cooking is a no-brainer for off grid folks, and on grid folks can benefit from the superior properties of gas cooking. Every chef worth his salt insists on only gas cooking, electric cannot compare! If I were totally off-grid, I would want to have wind, lower my power needs and produce pretty much what I need and not have a massive energy production infrastructure nor a massive battery arsenal. Why? Batteries require a lot of maintenance if you want them to last and serve you well. Here are some things to consider that you may have never been told:
PV Basics & Recommendations
Basics first- With an off-grid PV or PV/wind system, you have PV panels and/or windmills which feed into a charger/controller first, and then the energy is delivered into your battery arsenal. This charger/controller makes sure that your arsenal receives this energy at a controlled rate and voltage, and it protects your arsenal from becoming over-charged, which is crucial to your arsenals lifespan. Then, depending on the voltage you have designed your battery arsenal to be, you have the appropriate inverter which converts the power stored in your arsenal from whatever voltage it is at to whatever voltage you need for consumption, usually 115 volts, which is standard household voltage for everything except 220 volt things, which most people would not have if off-grid. Yes, there are panels with built-in inverters to give you 115 Volt power straight from that panel, but if you have a battery system off-grid, you must have a charger/controller, so it makes no sense to buy panels with that built-in inverter, that is strictly for on-grid PV systems, which do not require a charger/controller nor inverter, which is another compelling reason why on-grid PV-wind has huge advantages vs off-grid – it is less expensive, does not waste any energy produced and has no battery arsenal unless you want one for power outages at night. Now- our recommendations:
Keep it simple! 12 V inverters are not as efficient as 24 or 48 V inverters, BUT- a 12 V system means much more flexibility with your battery arsenal. Why? Because lead acid solar PV batteries are typically 6V per each battery, so making a 24 or 48 volt arsenal means a lot of batteries, and if one or more individual batteries start crapping out on you, they will drag the entire arsenal down to the performance of the worst battery, so that behooves you to change those bad ones out, then as time goes on, the arsenal in general inevitably looses performance, you change out the entire arsenal and go all over again. Of course, there are lithium ion batteries that are generally better than lead acid, but they ain’t cheap from what I have seen. Regardless of what kind of batteries you choose, with 12 volt systems, the whole battery scene is much cheaper and easier to maintain. Also, 12 volt inverters are a lot cheaper! What I recommend is using multiple inverters in the home- regular cheap ones for things that are not super sensitive to voltage fluctuations and sine-wave inverters for things that are. Most commercial PV guys like more centralized systems using a single 48 volt inverter whereas we kind of prefer decentralized systems that are configured with a little more thought involved in the systems design. The bottom line with off-grid systems is really evaluating your energy use, and minimizing it. The more you push electrons into and out of your arsenal, the faster you wear it out. Now you can probably see why we prefer on-grid support. That being said, we totally understand that folks like to get away from people, the government, utility companies etc. It is not a problem helping you with whatever objectives you have in mind, it just simply costs much more to live off-grid generally speaking, and is a lot more hassle and sacrifice. It can be done though, and it can be a fairly comfortable life if you plan it out nicely and thoroughly.
There are companies that make cool little units from highly modified automobile alternators that are around $400 more or less. You can purchase them one at a time and assess your needs as you go. Again, we cannot over emphasize the beauty of having power at night to keep that arsenal at a healthy voltage without running that generator. If you are in the Puna jungle, you most likely do not have enough wind to warrant the purchase. Folks in Hamakua, Kohala, South Point etc generally have tons of wind. There are a lot of things to consider when searching for that new location to build at. If that magic place is totally off-grid, go for it, and plan intelligently!
Other helpful info
LED lighting is very energy efficient and reasonably priced, making it an obvious choice for those off-grid. Every light source has its own feel and nature, so living on-grid does give you more options when it comes to lighting. Download an energy inventory form online and carefully evaluate the power consumption of your lighting and everything you use in your home. You will be greatly surprised at how much more you use vs what you think you use, and you will forever change the way you look at how you live your life. It is a great first step to becoming more efficient and green.
Let us know if we can help you sort thru your options, design and/or build your home, design and build your alternative energy system, water system, septic system etc, give us a ring or email us. We hope this information has been helpful to you!