Off-the-Grid Solar Power on the Blockchain in Brooklyn, NY. Part 1

Blockchain Technology Applications Off-the-Grid Solar Power Neighborhood Marketplace on the Blockchain in Brooklyn, NY. Part 1


People typically associate blockchain with cryptocurrencies and the financial industry and not with projects that run electric micro grids in local neighborhoods.

It is true that blockchain is the technology behind cryptocurrencies. The technology does enable users to transact with each other no matter where they are located in the world and do so at any time of day or night. However, “no matter where they are located in the world” does not necessarily mean “in the different parts of the world.” Blockchain can be a solution for local projects just it can be a solution for projects on a global scale.

Blockchain networks such as Bitcoin and Ethereum are decentralized, which means that there is no office with a central server, no physical location of Bitcoin that needs to be open, no authority that approves the transactions and so on. The Bitcoin and Ethereum networks are the authority.


Properties of blockchains: open-source, peer-to-peer, transparent

The software code of many blockchain networks is open source, meaning that anybody can download it, inspect it and use it. The information about transactions that occur on the blockchain networks becomes a part of a blockchain. On public networks such as Bitcoin and Ethereum, anybody can download a full copy of the blockchain. Such a copy would contain all the transactions that have occurred on the network since its launch.

A computer that contains a full copy of a blockchain on a network is called a node. For example, you can become a Bitcoin node by downloading a full copy of the Bitcoin blockchain from the official Bitcoin website here: A full copy of the blockchain is over 100 gigabytes in size. Downloading and installing it takes time and you can see the frequently asked questions about the process on the official Bitcoin blockchain website here:

While currently financial applications of the blockchain technology are some of the most well-known and popular, the technology is more than just about new currencies and people from different parts of the world sending money to each other. The data on the blockchain networks can be about anything, from movies to music to electricity usage. The blockchain technology is about peer-to-peer transactions, transparency and immutability, not about a specific application.

Peer-to-peer means that to transact on a blockchain network, whatever the network allows them to transact about, people do not need a third party. The network itself is a third party. Transparency means that anyone can see the transactions that have occurred on the network and can be sure that the record about the transactions is true and unaltered because blockchain records are immutable.


How blockchain technology works

In essence, a blockchain is a ledger. Depending on the network, this ledger can contain different kinds of information. For example, Bitcoin is a financial network and on the Bitcoin network the ledger contains information about Bitcoin transactions. On a social network Steem powered by blockchain technology, the ledger contains all kinds of information about posts, votes for posts, and more. You can see the explorer for the Steem blockchain at and the contents for one of the blocks at

Pages of the ledger are blocks of the blockchain. For example, on the Bitcoin network the pages of the ledger contain information about financial transactions. If you go to the official Bitcoin blockchain explorer,, at the top of the page you will see a table.

The very left column in the table is called “height.” Height of a block on a blockchain is the same as page number in a ledger, and the same as the number of the block on the blockchain. When Satoshi Nakamoto launched the Bitcoin blockchain in 2009, he has created block #1. Then, then network created block #2 and so on.

The number of the latest block that the Bitcoin network has created by the time you are reading this article will be in the top cell of the “height” column in the table at A block of the Bitcoin blockchain contains information about transactions that have occurred on the blockchain just like a financial ledger could contain information about transactions.

If you click on the height number of any block, the website will take you to the page of the block. At the very top you will see a table with a row “number of transactions.” This is the number of transactions that this very block (a page in a ledger) contains. For example, block #522205 contains information about 1291 transactions and you can see this information if you start scrolling down the page here