Saturday, May 20, 2017

Solar Panels

My wife and I recently bought a house in the San Francisco Bay Area. We are getting solar panels installed on the roof of the house. In this area it is a great financial investment - there is a lot of sun and the electricity rates are high. There is also a 30% federal tax credit for solar installations.

Determining the best size of the system to install depends on your electricity usage. Producing more power than you consume is less profitable.

We got quotes from three different companies. The quotes are surprisingly different:

SolarCity:
System size: 2.7 kW
Estimated annual production: 4,036 kWh
Cost before rebate: $11,394
Cost after rebate: $6,381
Price per watt: $2.36/W

Sunrun:
System size: 2.61 kW
Estimated annual production: 3,526 kWh
Cost before rebate: $10,559
Cost after rebate: $7,391
Price per watt: $2.83/W

SunWork:
System size: 2.61 kW
Estimated annual production: 5,050 kWh
Cost before rebate: $7,050
Cost after rebate: $4,950
Price per watt: $1.9/W

SunWork has by far the best price at $1.9/W. Not only that, but their system is estimated to produce far more kWh than the two other companies. Their system uses microinverters instead of a central inverter. Microinverters have a longer warranty: 25 years instead of 10 years. They are also more efficient than a central inverter. With a central inverter the system only produces as much as the least efficient panel. Microinverters allow each panel to independently perform the DC-AC conversion and also allow you to monitor the performance of each panel.

Another reason SunWork estimates a larger annual production is because they did a better job of optimizing the layout of the panels on our roof. Each company had a different layout:

SolarCity:


Sunrun:


SunWork:

SunWork managed to squeeze all nine panels onto southern facing parts of the roof. Sunrun had cool software which created a 3D model of our roof and automatically detected vents and surrounding trees (useful for modelling shadows). For all three companies the panel placement seemed to be done manually - combined with some software to estimate annual output.

Update: SunWork panels have been installed! Here is a dashboard to monitor our system output.

Update#2: The final price was lower than their initial quote: $6,565

2 comments:

Andrey said...

love the energy dashboard! very insightful

Emily Wonder said...

My daughter (Annabel) suffered from schizophrenia for 5 years. I had no idea what was happening and didn’t know where to turn for help. It was hard then because I really didn’t understand the symptoms earlier until she was diagnosed. There was a time she decided to get away from everyone, I was not excluded. I had to sit and cry almost every day because I felt helpless as a single mother (she is all I have got). The anguish I went through taking care of her alone is beyond explanation because there was no support whatsoever from the dad or family members. I fought for proper medical care and humane treatment; I did everything within my reach to get her cured but all to no avail. Countless different medications was prescribed (Zyprexa, fluphenazine, Risperdal, quetiapine, etc.) that she was taking but all we could get was myriad of side effects such as rigidity, drowsiness, dizziness, tremors and restlessness which tends to worsen the already damaged situation. Frustration was the order of the day. I wrote a couple of messages to the Ontario Mental Health Foundation for help because watching my daughter go through such was devastating. It was at this foundation someone shared a testimony about DR James herbal mix medicine, how effective it is and how she went through the most difficult times of her life trying to help her mom fight Schizophrenia. Being that I was already at the verge of giving up because I just couldn't imagine waking up every morning to fight the same demons that left me so tired the night before. I had to contact the Great  doctor, on his email  (GREATCUREMAN@GMAIL.COM)  from our conversations; I was relieved and convinced that the result is going to be positive because I was made to contact people with worse cases. Today, the awful situation of my daughter has gone by. Her happy life is back. She is now a schizophrenia survivor, and I am glad because my daily routine activities can now kick off without obstructions. Don't let Schizophrenia hinder you from living a desired life and also, never allow anyone to decide for you especially when they don't know what you have to go through to get to where you are. I was almost discouraged by the doctor but then, I remembered that: I have to shield my daughter’s destiny with courage, faith and perseverance because she is not in her right state of mind and that the bravery and freedom from fear is found in the ‘doing’. Her life is now a testimony. After my daughter got cured, from the herbal mix medicine Dr James prepared and sent to me, she said, Mom “I just thought, ‘Well, I’m a weirdo, I’ll never be normal, then I said, my daughter, life itself is a misery, and we get stronger in the places we have been broken. Thanks to you Dr. James  for your excellent counseling, no more psychotic symptoms for the past 3 years and 4 months now. To know more about Dr. James and the effectiveness of his Herbs and roots extracts, and he said he got cures for diseases like Bipolar, DIABETES, HPV, SHINGLES, CANCER, ALS, HEPATITIS B, KIDNEY DISEASE, HERPES, Ovarian Cancer, Pancreatic cancers, Bladder cancer, skin cancer, Prostate cancer, Glaucoma., Cataracts, Macular degeneration, Cardiovascular disease, Autism, Lung disease. Enlarged prostate, Osteoporosis. Alzheimer's disease, psoriasis, Tach Diseases, Lupus, Dementia. Kidney cancer, lung cancer. You can reach the Great Doctor on his Email at ... GREATCUREMAN@GMAIL.COM.  I believe you will testify just like me. INFO @ DrJAMESHERBALMIX@GMAIL.COM.