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GreyPower(P-)

Token
0x1e8e22c87811...a55a5ef21c18
DAO ForkSource VerifiedEdit this contract
Deployed August 20, 2016 (10 years ago)Block 2,105,928

GreyPower (P-), one of two tokens minted by an oracle-fed energy metering system, the other being GreenPower (P+).

DAO Fork EraVerified Source

Historical Significance

An attempt at settling electricity consumption on chain that splits the accounting into two tokens, one for green generation and one for grey, rather than a single balance. It also shows where a metering system has to place its trust: the parent contract can appoint oracles, and any oracle can mint either token to anyone.

Context

Deployed in 2016, when the advanced-token page on ethereum.org was the usual starting point for a token with an owner, mintable supply and account freezing. Energy settlement was among the applications proposed for Ethereum from early on, and this one is built on tutorial code rather than a purpose-written token.

Token Information
Token Name
GreyPower
Symbol
P-
Key Facts
Deployment Block
2,105,928
Deployment Date
Aug 20, 2016, 09:14 AM
Code Size
2.6 KB
Transactions by Year
20161

Description

A token in the ethereum.org advanced-token shape: an owner who can mint, freeze individual accounts and set a buy and a sell price at which holders trade with the contract itself, alongside transfer, transferFrom, approve and approveAndCall. It reports the string Token 0.1 as its standard, the name the tutorial used for the interface before ERC-20 took over.

This instance is named GreyPower with the symbol P- and zero decimals. It was not deployed on its own: a parent contract creates two of these in its constructor, GreenPower with the symbol P+ and GreyPower with P-, and keeps ownership of both. Accounts the parent has registered as oracles submit meter readings tied to a postal code, and the parent mints green or grey units to the household a reading belongs to.

Both tokens are created with a supply of zero, so every unit in existence was minted against a submitted reading.

Heuristic Analysis

The following characteristics were detected through bytecode analysis and may not be accurate.

Detected Type: Token

Bytecode Overview

Opcodes2,641
Unique Opcodes165
Jump Instructions126
Storage Operations77

External Links

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