Category Archives: Solar (Photovoltaic)

Home Power Optimization: the REbus™Microgrid

Home Power: Meet the REbus™ microgrid!

Run your decentralized Renewables efficiently and put them to use flexibly. From solar PV generation to micro wind turbines and battery storage, include even electrical vehicle charging and integration!

A REbus™ microgrid is a flexible energy network operating alongside the existing AC distribution network. Click for some specs and details. REbus™ is the ideal standard for connecting different sources of clean energy, including solar modules and small wind turbines, into an integrated hybrid system. The REbus™ standard makes it possible to more efficiently store clean energy produced on-site, and is ideal for charging electric vehicles quickly. The performance of each product on a REbus™ microgrid is easily monitored through a built-in communication layer.

Clean power micro grid system, decentralized clean energy, home power, micor wind turbines

The REbus™ DC microgrid is a great solution for anyone looking to generate clean renewable energy whether on-grid or off-grid. It easily and efficiently integrates PV, wind and other alternative energy sources, allowing a single inexpensive inverter to connect to the utility grid. The communications link gives renewable energy consumers instant access to data from each of their renewable energy devices for monitoring or diagnosis.

Converting the power coming from your renewable energy source to a REbus™ microgrid is significantly more efficient than the same conversion to a convential AC grid. Plus, the high voltage DC transmission means lower current in the connecting wires which improves the power transfer efficiency.

Because of the reduced electrical current in the wires, the cost of wiring is reduced.

The integrated power line carrier communication scheme eliminates the need for expensive and unreliable wireless communications. In todays insanely wireless world, it is a good idea to use wired communications instead of Wi-Fi. Wired communications provide increase security, less EMF radiation and less exposure of humans, decreasing adverse health effects of EMFs. Optional Ethernet communications are also available.

The overall efficiency and flexibility of the REbus™ microgrid system is significant, reducing cost of de-centralized Renewables generation and further increasing acceptability and potential of these technologies by improved usability.


Home Power as a Business: Using Renewables for Hedging Yourself Against Two Major Risks

Home power may very well save you during the upcoming economic downturn. It’s a bit like owning precious metals or “opting out” of our over-networked way of life in other ways. The beauty of investing in residential-scale Green Energy is its capability of hedging against two of the most likely economic risks threatening your money today: overall currency instability and consumer price inflation. These might materialize as soon as the end of summer 2012 and would likely be visible as a slight — and then accelerating — downturn and an increase in prices including energy and utility bills at one go. The supporting fundamentals for both are in place, it’s just a matter of time for them to materialize. As noted above, both are likely to happen rather soon (and yes, even though it may sound contradictory from a conventional economic point of view to have both a severe recession or even deflation and an increase in energy prices at roughly the same time, this is still a very likely scenario).

Click here to read more…


NEW: iPhone app monitoring Home Power systems

A new iPhone app for monitoring Home Power systems while on the move has been announced by Enecsys, a micro inverter manufacturer based in the U. K. and Germany.

The new iPhone app is compatible with all Apple iOS devices (iPhone, iPad and iPod touch) and displays generation information from Enecsys micro inverters. Micro inverters are a novel and efficient way of converting DC power from solar panels to appliance-grade AC (120 Volts/60 Hz in America or 230 Volts/50 Hz in Europe). Unlike central or string inverters connecting to an entire array of PV panels and requiring complicated and costly DC cabling, micro inverters plug in to one or two solar panels each and connect to the grid using ordinary plugs and a free socket.

Whereas central and string inverters usually require installation by a certified electrician, micro inverters are suitable for do-it-yourselfers as setup is easy and similar to plugging in a PC, radio or stereo equipment.

The new iPhone app makes monitoring of photovoltaic modules even simpler and more convenient. Launched at Intersolar Europe 2011 later this month, the app will be available direct from Apple’s iTunes store. Please register here to get notified once the app is released and available for immediate download.

Web Frontend Upgraded

The website has been upgraded to provide significantly better response times even during higher-volume traffic. With new — and despite higher CPU clock speeds and overall better specs even more energy-efficient — hardware, we have addressed past performance issues and hope to provide a better user experience for everyopne interested in Mini Wind & Solar Technologies.

UL Approval for Micro Inverters

Enecsys solar PV micro inverter becomes the world’s first without electrolytic capacitors to gain U. S. certification to UL1741 standard

Cambridge, U. K., January 8, 2011: Enecsys Limited, a solar PV micro inverter company, has announced UL1741 certification for its products. The patented design of the Enecsys micro inverter uses a rugged topology that eliminates electrolytic capacitors and opto-couplers, components that limit operating life and compromise reliability. Enecsys 240W micro inverters are the first micro inverters without electrolytic capacitors to achieve UL1741 certification. The same product is also certified for use in Europe, making Enecsys is the first company to introduce a truly global solar PV micro inverter. The inverter has an operating life expectancy of greater than 25 years, matching that of solar PV modules. This transforms the economic model of solar PV systems through greatly enhanced system reliability, energy harvest, ease of installation and improved system safety.

Solar PV systems based on micro inverters harvest from 5 to 20% more energy over the life of the system, compared to traditional string inverter based systems. In a micro-inverter based system Maximum Power Point Tracking (MPPT) is performed on each solar module and thus maximizing energy harvest even under partial shading, module mismatch or obstructions from leaves or debris. Systems are simpler to design and install and are safer because the high-voltage DC present in conventional solar PV installations is not present. No string inverter is needed because the DC output of each solar module is converted to AC using a micro-inverter mounted on the rack behind each module. This eliminates the central point-of-failure and the primary failure mechanism found in traditional inverters systems and micro inverters currently available in the market.

The reliability of Enecsys micro inverters has been verified using HALT, HASS and accelerated life tests to IEC61215, the same methodology used to test solar PV modules. The micro-inverters maintain full performance from -40 degrees C to +85 degrees C, ensuring efficient operation in real-world conditions. The Enecsys Wireless Monitoring System provides real time performance information for each solar module in order to maintain the high performance of the solar PV system throughout the operating lifetime.

The Enecsys micro inverter is designed to operate in both North American (60Hz) and European (50Hz) electricity grid systems. The micro inverters are safety and EMC evaluated to EN 62109, UL1741, TUV and CE. Country-specific requirements, including VDE V 0126-1: 2006 compliance, are achieved through the use of specific Enecsys installation products.

Using Home Power for Hedging Yourself in Two Ways

The beauty of a play in residential-scale Green Energy is its capability of hedging against both a general economic downturn and an increase in electricity prices at one go. Both are likely to happen rather soon (and yes, even though it may sound contradictory from a conventional economic point of view to have both a severe recession or even deflation and an increase in energy prices at roughly the same time, this is still a very likely scenario). The supporting fundamentals for both are in place, it’s just a matter of time for them to materialize.

Click here to read more…

Increasing Micro Generation Output: On-Board Micro Inverters

Micro inverters are a very innovative apporach to deploying truly modular solar PV systems.

A number of different micro inverter models have been developed lately, largely based on an innovation originating at Cambridge University and commercially developed by Enecsys. The Involar M-250 micro inverter is another implementation based on this concept, and while there is a certain smell to it, we are reporting on that latter product here. All micro inverters convert DC collected from a single solar panel or two into AC, tie PV modules together using AC connections rather than expensive and highly resistant DC connections, later transport the generated power to the grid, and usually also include components for monitoring power generation data. On top of the Involar M-250, we also offer the European-made Enecsys quality micro inverter models ranging from 200 Watts to 480 Watts and will add U. S. quality inverters in the near future. Enecsys inverters are fully UL-approved for the U. S. and Canada with the European models CE, UK G-83, German VDE 0126-1-1 certified.

The micro inverter concept has been developed in the U. K. by Cambridge University and launched to the market by Enecsys, Cambridge-based engineering firm


The following is quoted (and slightly polished) from the Chinese producer’s description:

A schmeatic overview of a micro inverter setup

The following steps elucidate the basic working princilples behind the INVOLAR micro inverter:

Step One

Solar photovoltaic modules convert light energy to direct current through the photoelectric effect.

Step Two

Micro inverters attached to photovoltaic modules finish the DC-AC conversion process.

Step Three

Synchronize and transport energy to the grid through phase-lock technologies with speed and precision.

Remark 1:Independent modules supported by micro inverters (250W) could form a parallel connection for a larger power requirement
Remark 2:MIS =Micro Inverter System

Features of the M250 Microinverter

      * Maximizes energy harvest – Different from conventional centralized inverters, M250 micro inverters conduct per-module MPPT, maximizing the efficiency of each single module with a consequent 25% increase in energy harvest.


      * Applicable to various conditions – M250 micro inverters allow for mismatch of photovoltaic modules, and each module can make flexible reactions to obstruction shading, inter-row shading, and obstacles such as dust or debris to avoid a sharp decrease in system efficiency.


      * Improved safety – With the built-in DC-AC conversion function, M250 micro inverters avoid dangerous HV DC circuits necessary to photovoltaic systems supported by conventional centralized inverters.


      * Fast problem diagnosis & solution – With PLC (Power Line Communications, i e electricity network) or WiFi technology, it is convenient to maintain real-time monitoring of every single module in the photovoltaic system.


      * Low failure rate – M250 micro inverter’s distributed framework ensures no single point of failure that would result in bringing the whole system down.


      * Plug-and-play installation – Free from the HV DC circuit, photovoltaic systems supported by M250 micro inverters could have fast, easy, and safe installation by allowing for PV module mismatch, a 15-25% decrease of installation time and cost, and flexibility in the changing of systems.


      * excellent INVOLAR M250 micro inverter is the result of the technical design with a high efficiency in its standard of air power supply, high power density, and high reliability.


      * By making use of the resonance soft-switching technology in MAC250 micro inverter’s main circuit, the switch frequency reaches near thousands of kHz, reducing wear and tear of the switch.


      * small, lightweight, high frequency transformer that achieves electrical isolation, power conversion, and high power density.


    * intrinsically safe current source hardware topology and high reliability.

Micro inverter technology by INVOLAR has resulted in a revolutionary device that is fully integrated into each individual module, converting DC to AC at the module level, with an independent MPPT function. INVOLAR’s micro-inverters outperform centralized inverters in:

1. Module-level Maximum Power Point Tracking (MPPT)

Different from the conventional centralized PV inverter, the microinverter enables each individual module to achieve MPPT, which allows for module mismatches and can harvest more solar power.

2. Increased Efficiency during the System’s Life Cycle

With the microinverter technology, the photovoltaic system receives a dramatically higher power output, more than 25% additional energy harvest in a less-than-ideal environment with possible obstruction shading, inter-row shading, and obstacles such as dust or debris.

3.Intelligence and Reliability

With the distributed microinverter framework, there is no single point of failure, which means that failure of any module will only affect its own performance and will NOT affect the other modules’ performances.

Involar’s unique Power Line Communication (PLC) and internet technologies enable real-time monitoring of every single module in the photovoltaic system for fast diagnosis and solution to a problem, thus improve reliability and system uptime.

We recommend switching off the integrated WiFi transmitters and use powerline communications instead in order to avoid potentially harmful EMF exposure; shield powerlines if necessary in order to insulate against powerline-transmitted high frequency signals. The full set of monitoring features is still available when using the less hazardous PLC and cable-Ethernet data transmission.

The INVOLAR remote monitoring system is based on a so-called ETU which is in effect a piggy-back box containing a data transmission unit. This unit is locked to transmit data to the manufacturer’s central data base on a proprietary protocol using internet protocol (high port 7001). If micro inverter user employs any sort of meaningful firewalling policy (blocking transmissions from the inside over non-standard ports) or if you just feel uneasy (actually, we do somehow…) to send your private solar energy data to some black box located in China and Chinese-controlled, you may want to use the “naked” micro inverter or multiple micro inverter units only.

Internet usage directives and Netiquette require every internet user to save bandwith and not flood the network or cause any jams by unnecessary usage. Transmitting a continuous data stream all the way to China is not exactly in line with proper internet use or common sense.

INVOLAR micro inverters can as well be run, and their other technical advantages such as increased output per panel can be used, without remote monitoring and without the “ETU” add-on. In order to lower installation cost — and in light of the above security considerations — you might be well-advised or simply want to go for such a bare-bones solution.

We do provide both solutions as an option, but feel it is our duty to be fair and raise the issue above for everyone to decide for themselves. In a simple consumer or Home Power setting the above issue may be less significant.

With or without the ETU the Involar M250 micro inverter enhances both modularity and configurability of solar PV arrays and, by eliminating DC line resistance, increase performance per solar panel up to 25%. Using a micro inverter, both accessory unit cost and maintenance cost can be decreased significantly in solar PV systems.

Micro inverters may also be used with micro wind turbines and is suitable for models from 50 W up to approx 1000 W rated power (depending on actual local wind conditions) when connected to a suitable regulator (or diversion or dump load). The Involar M250 along with the high-quality U. K.-manufactured Enecsys micro inverters are currently undergoing tests with LE-v50, LE-300 and the Airdolphin DC turbines.

Door Now Open for Feed-In Tariffs in the U. S.

The U. S. Federal Energy Regulatory Commission has ruled that U. S. states are free to enact their own feed-in tariff policies. This effectively clears the way for Feed-In Tariffs in the U. S. at state level similar to the ones in Germany or in the Province of Ontario. This decision by the chief regulatory body is expected to provide a further boost to Home Power and Renewable Energy as a whole on top of the already positive sentiment among U. S. consumers.

Latest polls show that up to 91% of consumers are in favor of Home Power generation and would be interested to set up their own systems sooner rather than later. The U. S. small wind energy sector has already experienced a 15% annual growth over the last years and is expected to accelerate even further. Equally bright are the prospects for Solar Power with improved technologies in solar thermal and CSP (concentrated solar power) as well as PV (photovoltaic or solar electric) generation.

Using Home Power for Hedging Yourself in Two Ways

The beauty of a Play in Residential-Scale Green Energy is its capability of hedging you against both a general economic downturn and an increase in electricity prices at one go. Both are likely to happen rather soon (and yes, even though it may sound contradictory from a conventional economic point of view to have both a severe recession or even deflation and an increase in energy prices at roughly the same time, this is still a very likely scenario). The supporting fundamentals for both are in place, it’s just a matter of time for them to materialize.

Click here to read more…

Can Airdolphin Power My Home?

Some of the most frequently-asked questions we receive is how much power to expect from mini wind turbines and if they can supplement in a meaningful way or even fully power an average home.

A very brief overview on what to expect in a real-life setting from a small wind turbine and how to expand energy output in a domestic setting.

This PDF leaflet is part of the downloadable information we provide free to registered website users.