Please visit
for new posts.

Thursday, June 29, 2006

bluespot offers free WiFi Internet access in Freiburg im Breisgau, Germany (also in Berlin and Dortmund)

bluespot is a great service for low security Internet tasks like email, browsing, and blogging, but I wouldn’t trust it for secure e-commerce transactions. You will need a functioning mobile phone to use the service. I know my German T-Mobile card phone works, but I do not know if GSM compatible phones with phone numbers from other countries are supported.

If you travel to Germany, getting broadband Internet access with a local access provider is a challenge or expensive or both. Free WiFi hotspots are rare or non-existent. Local access providers require a local telephone number and a service contract for home or mobile service in order to get flat or low cost Internet access. T-Mobile hotspots rates begin at 2 Euros per 15 minutes of uninterrupted, use or lose access for credit card walk-up (surf-in) customers.

When I first saw these bluespot kiosks, I was sceptical. What is the business angle? How do they make money on this? Will this result in some form of SMS spam? I will explore these questions later.

First, I had to register once with my mobile phone number, and a 4-digit PIN code was sent via SMS to my mobile. I registered at the kiosk, but it is also possible to register with your computer's browser.

Then, for each one hour WiFi Internet session, I had to enter my mobile phone number and the PIN code in order to obtain an access code via SMS. As the final step, the access code is entered into the start page and Internet access is confirmed. Of course, this last step must be done in the browser on the computer you wish to access the Internet!

After the one hour session expires, a new access code must be requested and entered into your browser in order to continue accessing the Internet.

bluespot is provided courtesy of Wall AG, a Germany company delivering city furniture and advertising kiosks to customers worldwide. Wall provides cities with free furniture and generates revenue by selling advertising space to companies. I believe the bluespot program leverages the Internet access requirments of the Wall information kiosks. In addition, I believe they may have plans for location based services and opt-in location push advertising to mobile phones in the future. To date, this bluespot service is only offered in the cities of Berlin, Dortmund, and Freiburg im Breisgau.

Thursday, June 22, 2006

PV Industry Forum 2006 in Freiburg Part 1

The 2nd PV Industry Forum was held yesterday in Freiburg im Breisgau, Germany, one day before the start of the Intersolar trade fair. In the morning session, there was a single program about “International PV markets: Status and development”. Regional solar market updates were first provided for Germany, California (apparently now considered a country), and Spain. Jens Herzog, SunTechnics, lauded the merits of California as the single, largest PV market in the US. I find it interesting that established California solar system integration and installation companies such as REC and Akeena are looking to expand and diversify their business in higher growth solar states such as New Jersey.

As teased yesterday, the presentation on “Silicon shortage: Overcoming the current bottleneck situation” by Prof. Dr. Peter Woditsch, CEO of Deutsche Solar AG (a wholly owned subsidiary of Solar World AG), made some compelling predictions and posed a key concern for future growth. In addition, although I thought Dr. Woditsch’s presentation might have had some technology spin, he avoided the marketing spin of many competitor presentations.

1) Dr. Woditsch believes raw silicon production expansion is in place to support 35% PV industry growth for the next 5 years. Silicon customers have directly invested and signed take or pay contracts with their silicon suppliers, shifting risk from silicon producers to their customers.

2) This translates into the potential for 8GWs of crystalline silicon solar production in 2010 (thin film production not included).

3) Dr. Woditsch predicted crystalline silicon will hold 90% or more PV market share in 2010 even with all the new thin film factories and production lines being built. He challenged the thin film firms to deliver competitive products in volume production - “Now or never”.

4) Also, Dr. Woditsch expressed concern about the development of new markets outside of Germany and Japan to fuel demand for this 8GWs of potential capacity.

5) Lastly, Dr. Woditsch stated his firm believes crystalline silicon solar modules have the potential for a 50% cost reduction from 2002 pricing through technology development efforts by no later than 2010.

Dr. Woditsch has thrown down the gauntlet to the thin film and silicon alternative solar manufacturers. Deliver compelling and competitive products than beat proven mono and polycrystalline solar technologies that are synergistic with the worldwide semiconductor industry

Wednesday, June 21, 2006

PV Industry Forum 2006 in Freiburg im Breisgau plus German WM win celebrations

First, I will post my interpretation of the PV Industry Forum 2006 tomorrow. In my opinion, the presentation by Prof. Dr. Peter Woditsch, CEO of Deutsche Solar AG, was the most interesting and dynamic presentation of the day long event.

Meanwhile, here are some photos of German soccer fans celebrating their national team's win against Costa Rica, 4-2, in the World Cup. The rise in German pride regarding their flag and team was reported this weekend in the New York Times (free registration may be required to access). The impromptu parade of people and cars would make American sports fan proud!

Sunday, June 18, 2006

Selected Reptiles and Amphibians from the New Jersey Pine Barrens

The New Jersey Pine Barrens (also referred to as the “Pinelands”) is a forested and rural area located in Southern to Central New Jersey. Even though New Jersey has the highest population density of any US state, the 1.1 million acres (4,500 km²) of the Pine Barrens remain underdeveloped. The Pine Barrens ecosystem thrives in the sandy, acidic, nutrient-poor soil typical of the region. The New Jersey Pinelands Commission is an independent, state/federal agency charged with preserving and protecting The Pinelands National Reserve.

Here are some of my friend's portraits:

Fowler’s Toad

This Eastern Garter Snake was interrupted while trying to chow down on another Fowler's toad. He was none too happy about the unnatural intervention! The Fowler's toad rested for about a minute and hopped as far away as it could.

These reptiles and amphibians are very common species. A thorough listing of Pine Barrens reptiles and amphibians with photos can be found at the Online Field Guide for Reptiles and Amphibians

One year, a few salamanders took up residence in our driveway. Alas, was not among them.
Disclaimer: I have no connection with , but I do enjoy Lurchi's Adventures.

Tuesday, June 13, 2006

Looking for technical publications about solar power inverters (wechselrichtern): design (MPPT), regulatory issues, and testing?

I started to research inverter technology for Grid connected PV systems earlier this year. The publications I found at US Department of Energy websites like The National Renewable Energy Laboratory (NREL) and Sandia Labs were short on length and technical details (because of public – private partnerships?).

pvresources has background information on inverters and highlights publications from industry and universities, many in association with the IEA Photovoltaics Power Systems Programme (IEA PVPS), regarding the history, regulatory evolution, and testing of inverters. Publications by Dr. Heinrich Häberlin and his associates at the Berne University of Applied Sciences, School of Engineering and Information Technology, are informative and worth reading. Most of Dr. Häberlin’s publications offer an English version, but there are German and French versions as well.

The best publication I have seen describing a MPPT Maximum Power Point Tracking approach is:

Development of a Microcontroller-Based, Photovoltaic Maximum Power Point Tracking Control System
Eftichios Koutroulis, Kostas Kalaitzakis, Member, IEEE, and Nicholas C. Voulgaris

provided courtesy of:





Texas Instruments (TI) has a webpage regarding Solar Power Inverters but the Application Report:

TMS320C2000™ DSP Controllers: A Perfect Fit for Solar Power Inverters (spraae3.htm, 10 KB) 05 May 2006 Abstract

is just an introduction without a companion reference design. Perhaps TI offers a reference design to their TMS320C2000 DSP customers?

Saturday, June 03, 2006

Vergulti Residence, New Jersey - The Solar Garden State

I plan to post an article about this attractive photovoltaic installation. For now, here are some of the technical details.

Location: Northfield, New Jersey

Solar System Size: 10.4kW

Panels: 52 x SunPower SPR-200 (200W)

Inverters: 3 x SunPower SPR-3200

These inverters are branded SunPower, but they are OEMing these from PV Powered. The switch located to the right is for DC cutoff.

Notice the shadowing caused by the chimney on the upper left roof of the house in the afternoon.